Kyōichi Katayama is a renowned Japanese author, born in Uwajima, Japan, on January 5, 1959. He gained both national and international fame with his novel Un grito de amor desde el centro del mundo (Sekai no Chūshin de, Ai wo Sakebu), which has sold over three and a half million copies in Japan, making it the best-selling Japanese novel and establishing him as one of the most prolific Japanese writers of the 21st century.

Katayama was born in the Ehime Prefecture and graduated from Kyushu University. His first major book was Kehai (Sign), which won the Bungakkai Newcomers award. His work Socrates in Love (also known as Crying Out Love, In the Center of the World) was adapted into a manga, a film, and a Japanese television drama. As of 2008, it remains his only book translated into English.