Alien Robuton (ロブトン星人 Robuton Seijin) was a small time alien criminal that appeared in ULTRAMAN.
Alien Robuton had killed several people, gaining the attention of the SSSP, who sent a team to exterminate or capture it. While tracking it down, Dan Moroboshi and his team found an impaled security guard in a warehouse before being attacked by the alien, who launched spikes at them. Shinjiro Hayata then arrived to deal with the alien, slamming it onto the floor, but it altered its appearance to look like Rena Sayama, pleading him not to make the kill. Finding himself unable to finish off the alien, Shinjiro allowed the rest of the team take it into custody.
- Height: 110 cm
- Weight: Unknown
- Origin: Unknown
- Powers and Weapons
- Spikes: Alien Robuton is able to launch spikes out of its holes, with enough force to impale a person.
- Illusion: Alien Robuton was able to change its appearance.