Custom Robo (カスタムロボ, Kasutamu Robo^?) is a science fiction robotic fighting video game franchise developed by NOISE and published by Nintendo Co., Ltd..

The series currently spans five games, and has titles on the Nintendo 64, Nintendo Game Boy Advance, Nintendo GameCube and Nintendo DS. The most recent title in the series was first released in Japan on October 19, 2006, while it was later released in North America on March 19, 2007, in Europe on May 25, 2007, and in Australia on September 20, 2007.

Since its inception in 1999, the Custom Robo series has largely been confined to Japan. In 2001, however, Nintendo released Super Smash Bros. Melee, a fighting game containing characters from throughout the company's history, worldwide. In the title's trophy room, three custom robos from Custom Robo V2 appeared as trophies: Ray Mk II, Bayonette, and Annie.

According to the upcoming release lists in several issues of Nintendo Power, Nintendo of America was planning to release Custom Robo GX, the third title in the series, but later canceled it for unknown reasons and decided to release Custom Robo: Battle Revolution, the fourth title in the series, which became the first to see an international release, in 2004. Released outside of Japan simply as Custom Robo, the game was designed specifically with newcomers to the series in mind. The fifth title of the series, Custom Robo Arena, became the first and only Custom Robo title released globally.