Akiko Fukuoka & Eriko Hashimoto performing live, 2011.

chatmonchy (チャットモンチー, chattomonchī) was a three-piece all-female rock band which consisted of Eriko Hashimoto (guitar, vocals), Akiko Fukuoka (bass, chorus), and formerly Kumiko Takahashi (drums, chorus) who are from Tokushima Prefecture on the island of Shikoku, Japan.

Since 2005, they were signed to Sony Music Japan's Ki/oon Records record label. In November 2017, the band announced that they were disbanding.

The band had their final one-man concert on July 4, 2018, at the Nippon Budokan, and held their last "Konason Fest" on July 21 and 22.