Irem (アイレムソフトウェアエンジニアリング株式会社 Airemu Software Engineering) is a Japanese video game console developer and publisher, and formerly a developer and manufacturer of arcade games as well. The company has its headquarters in Chiyoda, Tokyo. The full name of the company that currently uses the brand is Irem Software Engineering. It was established in 1997 by its parent company Nanao for the purpose of taking over the development department of the original Irem Corporation, that had left the video game industry in 1994 to concentrate itself on the rental and sales of coin-op electronics. Irem Corporation was founded in 1974 as IPM and still exists today under the name of Apies.

Irem is probably mostly known internationally for three 1980s arcade games Moon Patrol (1982; licensed to Williams Electronics in North America), the earliest beat 'em up, Kung-Fu Master (1984), and the scrolling shooter R-Type (1987). Irem has been popular in Japan with games like Photoboy for the PC Engine and In the Hunt for arcades. As a result of the 2011 Tōhoku earthquake and tsunami, Irem canceled the majority of its remaining video game projects, including Zettai Zetsumei Toshi 4 Summer Memories and Poncotsu Roman Daikatsugeki Bumpy Trot 2. Irem refocused to become primarily a slot-machine and pachinko developer, the industry it was in before turning to video games. Many Irem designers, including producer Kazuma Kujo, gathered to form a new company called Granzella to continue creating video games.