The WonderSwan is a handheld game console released in Japan by Bandai. It was developed by Gunpei Yokoi's company Koto Laboratory and Bandai. Released in 1999 in the fifth generation of video game consoles, the WonderSwan was officially supported until being discontinued by Bandai in 2003.

During its lifespan, no variation of the WonderSwan was released outside Japan.

Powered by a 16-bit central processing unit, the WonderSwan took advantage of a low price point and long battery life.

The WonderSwan is playable both vertically and horizontally, and features a unique library of games, including numerous first-party titles based on licensed anime properties, as well as significant third-party support from Square, Namco, and Taito.