J-ta Yamada is a Japanese manga artist and illustrator. Born on January 26 in Kisarazu City, Chiba Prefecture, Yamada is known for creating the manga series Asatte no Houkou, which was adapted into the anime television series Living for the Day After Tomorrow. The original manga was serialized in Mag Garden's Comic Blade Masamune magazine from March 2005 to June 2007, spanning five bound volumes. The story, which involves a young girl who transforms into an adult and an adult woman who reverts to a child, was adapted into a twelve-episode anime by J.C.Staff that aired from October to December 2006. For this adaptation, Yamada was credited as the original creator and also provided character design assistance.

Beyond this work, Yamada has created other manga series including Majina! and Gifuto. Yamada also contributed a manga to the anthology Code Geass: Lelouch of the Rebellion — Knight: Official Comic Anthology For Girls, Volume 1. As an illustrator, Yamada has provided cover art for the Hayakawa Bunko edition of the light novel JK Haru is a Sex Worker in Another World and serves as the artist for its manga adaptation. Yamada's illustration work extends to card illustration for various games, including Aquarian Age, Kemomimi Panic, Kuni Tori! Gaiden, and Tanto Cuore: Romantic Vacation. Additionally, Yamada created a mahjong game titled Higurashi no Naku Koro ni Jong, based on the Higurashi When They Cry series, which was serialized in Takeshobo's Kindai Mahjong magazine starting in 2010.