Mazinger Z (Japanese: マジンガーZ, Hepburn: Majingā Zetto, known as Tranzor Z in the United States) is a Japanese super robot manga written and illustrated by Go Nagai. It was originally serialized in Shueisha's Weekly Shōnen Jump from October 1972 to August 1973 and Kodansha's TV Magazine from October 1973 to September 1974.

Mazinger Z has since spawned a media franchise. It was adapted into an anime television series by Toei Animation, which aired on Fuji TV from December 1972 to September 1974. A second manga series was released alongside the TV show, this one drawn by Gosaku Ota, which started and ended almost at the same time as the TV show. The series was followed by several sequels and spin-off, among them being Great Mazinger, UFO Robot Grendizer and Mazinkaiser. Mazinger Z: Infinity, a theatrical film sequel, taking place ten years after the Great Mazinger series, was animated by Toei Animation and released in theaters on January 13, 2018.

Although not exactly the first Mecha anime in history, the series has often been cited as being the first modern one.