Aquaplus (株式会社アクアプラス, Kabushiki gaisha Akuapurasu), formerly U-Office (ユーオフィス, Yū Ofisu) and Aqua (アクア, Akua), is a Japanese company which specializes primarily in the publishing and distribution of visual novels, including both adult games under their brand Leaf and games for all ages under Aquaplus's own brand.

Aquaplus was established in October 1994 in Itami, Hyōgo, Japan as a visual novel and music publishing company at the time called U-Office, ltd. (有限会社ユーオフィス, Yūgengaisha Yū Ofisu); their adult game brand Leaf was also established at this time.

Albums released in connection with the visual novels the company publishes are also recorded at Studio Aqua.

Aquaplus had managed an automobile specialty shop in Taka, Hyōgo, Japan called Aqua, but closed it down on August 31, 2007.

Aquaplus offered downloadable freeware titles such as Multi's Going Out, Black Wings, TANK BATTLE, Ojomajomini, Inagawa de Urou!