Tanikawa has written more than 60 books of poetry in addition to translating Charles Schulz's Peanuts and the Mother Goose rhymes into Japanese.

Since the 1970s, Tanikawa also provided short, onomatopoeic verses for picture books he published in collaboration with visual artist Sadamasa Motonaga, whom he had befriended during his residency in New York in 1966, offered by the Japan Society.

[5] Tanikawa also co-wrote Kon Ichikawa's Tokyo Olympiad and wrote the lyrics to the theme song of Howl's Moving Castle (film).

Together with Jerome Rothenberg and Hiromi Itō, he has participated in collaborative renshi poetry, pioneered by Makoto Ōoka.

The author-illustrator Yōko Sano was his third wife, and illustrated a volume of his poems: Onna Ni, translated by William I. Elliott and Kazuo Kawamura (Shueisha, 2012).