|This article is about an ally in Denji Sentai Megaranger.|
Jirou Iwamoto (岩本 ジロウ Iwamoto Jirō) is a student of class 3-A of Moroboshi High School and classmate of the five Megarangers. He usually is seen alongside his friend Shintarou Wada, particularly helping his friend attempt to win over the heart of Miku Imamura. Jirou became friends with Shintarou as children when the larger-set male befriended him after being bullied by others.
During the Hell Nejilar incident where a Psycho Nejilar attacks Moroboshi High and the Megarangers' true identities are revealed to their fellow students, Jirou gets hurt in the midst of the defense of the school, making him hospitalized and making the five scorned by their classmates, including Shintarou. Only when Jirou returns from the hospital to cheer his fellow students on during their final battle with Dr. Hinelar does Shintarou finally get over the scorn, allowing for the team to have the support to stand up and defeat the mad doctor before graduating from Moroboshi High.-
- Jirou is portrayed by Takumi Hashimoto, who is most notable for having portrayed Dime Tribe Knight Boi (TigerRanger) of Kyōryū Sentai Zyuranger.