Tetsujin 28-gō (Japanese: 鉄人28号, Hepburn: Tetsujin Nijūhachi-gō, lit. "Iron Man No. 28"), known as simply Tetsujin 28 in international releases, is a 1956 manga written and illustrated by Mitsuteru Yokoyama, who also created Giant Robo. The series centers on the adventures of a young boy named Shotaro Kaneda, who controls a giant robot named Tetsujin 28, built by his late father.

The manga was later adapted into four anime television series, a Japanese television drama and two films, one live action and one animated. Released in 1963, the series was among the first Japanese anime series to feature a giant robot. It was later released in the United States as Gigantor. A live-action movie with heavy use of CGI was produced in Japan in 2005.

The series is credited with featuring the first humanoid giant robot controlled externally via remote control by an operator.