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Sergeant Keroro is the Captain of the Space Invasion Forces Special Advance Team of the 58th Planet of the Gamma Storm Cloud System, sent to the planet Pokopen (aka Earth) to collect intelligence for his planet's invasion force. He is also a frog. After his ship crash-lands in the planet earth, he takes shelter in the Hinata household, but the two kids, Fuyuki and Natsume, find him and take away his alien weapons. When his people discover that the Pokopenians are aware of him, Keroro is abandoned - left to fend for himself in this hostile world. But he's not alone - four other pre-invasion agents were are also lurking on Earth. It's invasion of the weird in this wacky comedy hit!

Close Encounters of the Green Kind!



Sgt. Keroro, commanding officer of Planet Keron's invasion force, has a problem. After blowing his cover and losing his top-secret weapon, the frog-like alien has been cut off from his homeworld. To make matters worse, he's lost communications with the rest of his platoon. Now he has taken cover in the Hinata family household, where in exchange for doing his share of the chores, he gets his own room from which to secretly devise new plans for world domination!

188 pages, Paperback

First published January 1, 1999

21 people are currently reading
392 people want to read

About the author

Mine Yoshizaki

87 books18 followers
From Keroro Wiki:

Mine Yoshizaki (吉崎 観音 Yoshizaki Mine), born December 2, 1971 in Isahaya, Nagasaki) is a male Japanese manga artist (mangaka) who first started his career by making dōjinshi based on video games. Yoshizaki also worked as an assistant to mangaka Katsu Aki . His first publication was featured in a compilation book published by Shogakukan in 1989.
He is best known for his manga Keroro Gunso, published as Sgt. Frog in the United States, which was first published in the Japanese manga magazine Shonen Ace. He is also the creator of Arcade Gamer Fubuki and did character design on the series Seven of Seven. In 2005, Keroro Gunso received the 50th Shogakukan Manga Award for children's manga.

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5 stars
270 (36%)
4 stars
221 (30%)
3 stars
165 (22%)
2 stars
51 (6%)
1 star
28 (3%)
Displaying 1 - 30 of 54 reviews
Profile Image for Varek.
7 reviews
May 10, 2025
KERO KERO
Un anime de mon enfance que j'ai décidé de lire dans sa version originale. Le manga est plutôt fidèle à celui ci et même drôle par moment ! Cela dit, je ne suis pas fan des plans culottes en général. Heureusement que l'anime a été plus ou moins censuré à ce niveau là !
138 reviews
July 19, 2025
I bought this at a Barnes and Noble clearance like a million years ago and it’s just been sitting on my bookshelf ever since. Recently I read something from a manga author I like (I think it may have been Keiichi Arawi?) saying they had fond memories of reading Sgt Frog. Unfortunately, now I can’t remember who it was or where I read this. Wow, this review isn’t off to a great start.

ANYWAY, this is … fine. It has a very clear 1990s / early 2000s art style, and a very silly, fairly juvenile sensibility. I like silly writing when it’s well done, but in this manga, it seems kind of pointless and not particularly funny to me. It’s probably not bad, just didn’t click with me (probably because the target audience is young teenagers).
Profile Image for Fabio.
391 reviews5 followers
June 28, 2021
Keroro e' una piccola rana spaziale con una stella sul pancino che ci conquistera' tutti (sia letteralmente che nel nostro cuoricino). Divertentissimo e molto fresco. Non vedo l'ora di leggere i prossimi. Peccato sia disponibile solo in digitale!
Profile Image for D.M. Dutcher .
Author 1 book50 followers
November 11, 2012
It's not as good or as funny as you'd think, and it really depends on how much you like Otaku culture of the 2000s. This review is of the series, as it's more than eighteen volumes.

Fuyuki's an average boy with an interest in the occult. Unfortunately he's about to have uninvited guests. A frog-like alien with an unhealthy obsession with Gundam models plans to find his buddies and take over the earth-that is if he ever gives up freeloading off of Fuyuki's family first. A lot of random weirdness ensues.

The big problem is that most of the frog aliens are really annoying. Sgt. Frog himself grates on your teeth, and really only Giroro and Dororo are likable. The other characters range from meh, like Fuyuki, Natsumi's mom and Moa, to okay like Natsumi herself, to pretty hilarious like Momoka, Paul (who steals the show often,) and Momoka's mom. Unfortunately they don't really grow or anything, and it's just a collection of stories rather than a fulfilled series.

What will attract you to this is the massive amount of anime and otaku references. Most of these are based around japanese culture circa around 2005, and are going to get dated, fast. But if you like that there's so much self-reference that it's going to evoke nostalgia more than humor. Seeing Momoka in a Chun-li dress and her Mom in Chun-li's SF alpha costume, for example. A pretty funny one is how Natsumi is tough and a little violent, but her videogame of choice is a clear Animal Crossing clone. Street Fighter references abound, Gundam is a virtual religion in the series, and there's no shortage of references.Even Rei Ayanami pops in.

Some of the strongest ones are self-referential. Early on, a few cast members from his early anime Seven of Seven show up, and that's a big draw for fans. It takes 19 volumes to get the Nanas to show up though. Arcade gamer Fubuki also makes an appearance.

Other than that it's really not as funny as it could be. Momoka is a great character, with her split personality, and her protective butler Paul is a riot who tears his shirt off and busts out dragon punches and mad drumming skills at a moment's notice. But really the rest is a little too otaku-centric and random to get more than the odd chuckle. It's more fun to remind you of what you were doing 7 years ago than as a comedy series.
Profile Image for Amy Keeley.
Author 17 books22 followers
January 5, 2012
This is a great little comedy about a frog-like alien who gets stranded with his team on earth after a botched invasion attempt and "captured" by a young boy and his family. The frog's various attempts to get the upper hand on his captors/friends (you're never really sure which it is) are hilarious and his determination to continue the invasion...well, you don't know whether to laugh at him or cheer for him. It doesn't help the "invasion" that he begins to show signs of being manga-obsessed. However, it isn't until the appearance of "multiple personality" afflicted Private Tamama (another alien of the same species) that the story really takes off. (Note: the book describes him as having multiple personalities but I think he's just mercurial regarding certain aliens.)

There's a fair amount of fan service in this volume, mostly panty shots, but nothing that detracts from the story itself. It's a good laugh and a nice twist on the end of the world as we know it.
Profile Image for Shannon.
32 reviews4 followers
January 27, 2013
A frog from outer space that builds Gundam models? How can I not love this manga?!
Profile Image for Nazish Ahmed (Nazish Reads).
953 reviews38 followers
September 11, 2022
I bought vol. 2 from a convention years ago. I got it from a used manga table along with a few other manga volumes. At the time, I just wanted to have as much manga as possible. Nowadays, I have almost 700 volumes and I’m older, so I don’t buy random volumes anymore, even when they’re really cheap, I only buy ones that I’m really interested in. Because I had vol. 2 for years, I decided to finally read vol. 1 and 2 and see if I want to continue reading it and buy the rest of the series (which is 32 volumes long and out of print, so it won’t be easy) or if I just want to continue reading it but not buy the rest of the series.

Overall, this seems like a cute and fun story. I’m not sure how I feel about the characters yet. I don’t remember if I’ve ever read a manga series with main characters this young (I have Kodacha but I haven’t read it yet), but I have watched anime with elementary school main characters years ago: Kodocha and Cardcaptor Sakura (really want to read the manga eventually). There were lots of 90s manga and anime jokes and also jokes on being a man Gaia, which I found interesting, some were funny some weren’t.



Blog: nazishreads.net/TravelandBookBlog
Twitter: Naz_readsanime
Instagram: nazishreads, nazcosplay, nradesigns, charmedanimegirl01
18 reviews2 followers
September 17, 2018
Rating: 6 out of 10
Violence: Low (Occasional burning to cartoon type cinders)
Fan service: Moderate (Lots of cleavage)
Sexual Content: Low (Talked about occasionally)
Type: Imbecile Alien Antics
Read: 2 Volume
More?: No
Plot Analysis: Sgt Frog is part of a forward team of aliens who were coming to take over the world. On his accidental discovery, however, the invasion plans were scrapped and he was left on Earth to fend for himself. The brother and sister who discovered him kept him, making him part of their family, one as a friend and the other with deep suspicion. Antics ensue.
Review: Frenetic. I rather liked the oddity of it, but its use of cleavage as a break between (and in the middle of) antics is a bit annoying. Aside from introducing new characters almost every chapter, I’m hoping for more character development. The characters are fairly one dimensional, from the full-chested mother to the friend who goes from timid to furious and back at the drop of a frame.
Profile Image for David Doel.
2,436 reviews6 followers
January 9, 2023
This series has great potential -- a brother and sister are suddenly hosting an alien who plans to conquer the earth. That alien looks like a frog and regularly trips over its shoelaces. Better yet, Mom is a mangaka who sees potential stories from the situation.

Unfortunately, this mangaka (Mine Yoshizaki) feels the need to add a love story to the mix and give it too much air time. I hope he will aim his attention more to the bumbling alien than to the bumbling girl in the remaining 19 volumes I'm about to read.
Profile Image for Nanang Stiawan.
302 reviews
October 31, 2021
Dulu kirain ini komik untuk bocah haha karena covernya sangat TK TK banget.

Gataunya isinya gk cocok dibaca anak2. Karena guyonannya berat dan gak bakal lucu kalo gak punya referensi. Ditambah karakter seksi mama Hinata yg bikin puyeng😁

Grafik duel2nya jg seru bgt sih ini. Lengkap pokoknya
Profile Image for Brenna.
936 reviews1 follower
June 27, 2019
What a fucking weird amazing series. Those frogs are still damn cute
Profile Image for ISMOTU.
804 reviews2 followers
November 15, 2019
A fun little manga about a frog-like alien invader who is adopted by a Japanese family and hi jinx ensue. Cute and silly.
11 reviews2 followers
August 22, 2021
Interesting story, all-too-often distracted by sexualising female characters, including teenagers.
Profile Image for Blake Herondale.
329 reviews3 followers
September 6, 2024
No es para mi, me parece demasiado absurdo todo y no puedo con el bicho rana este. No he podido ni acabar el tomo
Profile Image for syifa juliawan.
55 reviews3 followers
August 3, 2025
Lucu sih tp gambarnya banyak yg inappropriate padahal karakternya anak perempuan usia 13 tahun
Profile Image for Hazel Jamieson.
31 reviews
August 13, 2025
Utterly shit just utterly shit. While some of the comedy is good, so much of it is just perverted or sexist and I couldn't stand how all of the women basically just exist to be ogled, even the mum. One of my least favourite shonen i've read and that's saying something
Profile Image for Robert Beveridge.
2,402 reviews199 followers
April 18, 2011
Mine Yoshizaki, Sgt. Frog, vol. 1 (Tokyopop, 1999)

What is this thing the Japanese have with taking incredibly cute, cuddly anthropomorphic animals and making them want to conquer the universe? (Think of Kon, the stuffed teddy bear in Bleach, for an obvious example.) It was inevitable that one of those cute, cuddly sadists would eventually get his own manga. Mine Yoshizaki obliged with Sgt. Frog, a series that has been successful enough on both sides of the Pacific to run to over twenty volumes (and an adapted anime still going after three hundred fifty-plus episodes as of this writing). The basic plot: Keroro, the leader of a platoon of frog-like aliens, brings his troop to Earth as an advance scouting team, to see if the planet is worth taking over. Something goes badly wrong, and their ship leaves, stranding them scattered around Japan. Keroro is soon discovered by the Hinata family, and after some quick negotiations, is offered the attic room, where he spends his time building models and surfing the net when not plotting to take over the planet—because after all, how could he do that without the rest of his platoon? But one of them could be closer than they think... cute, very witty, and all kinds of meta (the number of pop-culture references in here is stunning), it's a fun beginning to a series I hope stays this good. *** 1/2
Profile Image for Ace.
478 reviews12 followers
April 5, 2016
I tried to like this, I swear. I think I need to stop reading comedy!

Fuyuki is an average middle schooler until he and his sister Natsumi discover an alien living in their house. Sgt. Keroro is in Japan on a mission to take over the world until he ends up on house arrest with Fuyuki's family, doing chores in exchange for a room. The premise is wacky, the humor is silly, the fourth wall is often broken, and I couldn't get over how similar Natsumi looked to Ace from the Mario Tennis GBA video game.

(Seriously, go look: http://www.mariowiki.com/images/thumb...)

See it?

Unfortunately, the boob weirdness spoiled it for me. There were way too many panty shots, boob shots, girls in skimpy clothes, etc. for me to enjoy what I was reading. I mean, c'mon, Natsumi is like 14 years old. That's gross. And their mom is over-the-top ridiculous, even for a comedy. I didn't feel like the characters grew or changed at all during this volume.

Not my cup of tea.
21 reviews
May 31, 2011
This book is about an unspecting family finding an alien invader (Keroro) in the brother's (Fuyuki) room. Natsumi (the big, stronger, athletic, tempermetal) sister beats him up, the mom (aki) lets him stay and he becomes the family house cleaner. But hes not the only one theres 5 invaders of the keroro platoonand find Tamama (easly jelous, cute sweet loving, in love with Keroro) with a rich girl whos in love with Fuyuki (momokaz Nishezawa (spelling might be off)) who like Tamama has a split personality. They go on a vaction where Momoka tries to get closer to Fuyuki. When they come back they meet the peson who was supposed to destroy the earth and it turns out shes good friends with Keroro (she likes him) so she ends up joining them.
Profile Image for Dave.
Author 61 books124 followers
June 21, 2008
This is a really funny Manga series that can easily be compared to the amercian cartoon show, Invader Zim. The main characters are very similar in motivation and distraction! The art and character designs for Sgt. Frog and most of the cast are great. It would be a good all-ages series if it wasn't for the jiggly "fan service". Nothing too racy but definitely questionable. Is that doesn't both you then check out the series for sure!

Sgt. Frog is one of the most iconic and memorable characters I've come across in Japanese comics. When I see him around at comic conventions it puts a smile on my face.

Profile Image for Louie.
17 reviews
July 25, 2008
I knew SGT Frog since I was 8 years old. I lived in South Korea, so I used to watch it on TV. And I thought that it was hilarious. But I didn't know these comic books of the series even exist before I landed on a bookstore last week.

All I have to say is, really, it's a fun and a cute book. It's about these army of Frogs who comes to Earth to invade it and make it their own place, but their plan eventually fails as Keroro, the leader, lives with human beings and makes a friendly bond with them.

SGT Frog, along with Naruto, is a memorable and friendly comic to just entertain yourself while reading it. The comic series, and the cartoon, overall, is awesome.
Profile Image for steven XD.
11 reviews1 follower
January 26, 2010
Sergeant Keroro is the Captain of the Space Invasion Forces Special Advance Team of the 58th Planet of the Gamma Storm Cloud System, sent to the planet Pokopen (aka Earth) to collect intelligence for his planet's invasion force. He is also a frog. After his ship crash-lands in the planet earth, he takes shelter in the Hinata household, but the two kids, Fuyuki and Natsume, find him and take away his alien weapons. When his people discover that the Pokopenians are aware of him, Keroro is abandoned - left to fend for himself in this hostile world. But he's not alone - four other pre-invasion agents were are also lurking on Eart
Profile Image for Werehare.
771 reviews29 followers
August 16, 2015
(recensione unica per tutta la serie) Divertentissimo. I personaggi degli alieni sono esilaranti, e le loro avventure tragicomiche non possono non strappare una risata. La struttura a episodi implica inevitabilmente degli alti e bassi di trama e comicità, ma nel complesso il fumetto resta godibile. E’ letteralmente disseminato di citazioni che spesso solo gli “addetti ai lavori” riescono a cogliere, ma riesce a far ridere anche una ignorante di cultura giapponese come me. Alcuni personaggi (femminili) umani Sueizzano, rimandando alla dimensione prettamente shonen-ai. Il disegno è pulito e curato, e presenta una notevole evoluzione dai primi volumi.
Displaying 1 - 30 of 54 reviews

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