Jimsaku (ジンサク, Jinsaku) is a Japanese drum and bass duo formed by Akira Jimbo and Tetsuo Sakurai in 1990, after they left the jazz/fusion band Casiopea.

[2] To try to fix this issue, any and all support members of the group were removed,[3] leaving just Sakurai and Jimbo.

Around this time, live performances shifted, after the support members left, concerts became just Sakurai and Jimbo on stage.

[7] After Jimsaku's 30th anniversary, and their new album, the band started playing shows with fellow ex-Casiopea member, Minoru Mukaiya, who was not allowed back into the group after Casiopea's reunion in 2012.

The three formed Katsushika Trio in 2022, which at first was dedicated to playing Casiopea songs from the 80s, but has released 4 singles, an EP, and 2 LPs.