Louis Slobodkin entered the Beaux Arts Institute of Design, where he studied drawing, composition, and sculpture, at the age of fifteen. In his six years there, he won over 20 medals for his work, and was awarded the Louis Tiffany Foundation Fellowship.
In 1927, Slobodkin married Florence Gersh, a poet and children's author. However, Slobodkin did not become involved in children's literature until 1941, when he illustrated The Moffats, by his friend Eleonor Estes.
In 1944, Louis Slobodkin won the Caldecott Medal for illustrating Many Moons, written by James Thurber.
During his career, Slobodkin illustrated nearly 90 books, 50 of which he also wrote. He and his wife collaborated on five books.