It was serialized in Kodansha's shōjo manga magazine Dessert from February 2008 to July 2017, with its chapters collected in 18 tankōbon volumes.

Written and illustrated by Kanae Hazuki, Say I Love You was serialized in Kodansha's shōjo manga magazine Dessert from February 23, 2008,[3] to July 24, 2017.

The limited edition of the eleventh manga volume, released on July 24, 2013, was bundled with an original animation DVD (OAD).

[46][47] The wraparound jacket band of the 11th volume of the manga announced in 2013 that a live action film was greenlit for release in 2014.

[49][50] Additional cast members include Tomohiro Ichikawa as Kai Takemura, Rika Adachi as Aiko Mutō, Tasuku Nagase as Takeshi Nakanishi, Rima Nishizaki as Asami Oikawa, Ryōsuke Yamamoto as Masashi Tachikawa, and Arisa Yagi as Megumi Kitagawa.