He joined Johnny & Associates in October 2006 without auditioning.
In 2007, joined Jr. unit Tap Kids, where his brother Morimoto Ryutaro belonged to as well.
In 2012, he acted in Shiritsu Bakaleya Koukou with Kochi Yugo, Kyomoto Taiga, Matsumura Hokuto, Jesse and Tanaka Juri. Although an unofficial unit, the six found large popularity as Bakaleya6 (the name originating from the drama). It was not until Johnny’s Ginza 2015 that Bakaleya6 was introduced as an official unit under the name SixTONES.
On August 8, 2019 it was announced that SixTONES and Snow Man will simultaneously make their CD debut in 2020.
He graduated from Horikoshi High School in the spring of 2016.
- Name: Morimoto Shintaro (森本慎太郎)
- Nicknames: Shin-chan, Shinchaman, Shintarosu, Goritaro
- Birthdate: July 15, 1997 (24)
- Western Zodiac: Cancer
- Eastern Zodiac: Ox
- Birthplace: Kanagawa, Japan
- Blood Type: A
- Height: 175 cm
- Weight: 65 kg
- Admired Sempai Takizawa Hideaki
- Hobby: Soccer,reading manga,games
- Skills: Soccer, Karate, bseball
- Favorite Sport: Soccer
- Favorite Color: Black,Red
- Favorite Food: Salmon sushi.
- Dislike: Vegetables
- Favorite Drink: Cola
- Favorite type of girl: Cute, friendly
- Favorite Song: "Everything" by Arashi,"Kimagure JET" by Takizawa Hideaki and "Kisek" by Takizawa Hideaki
- Favorite Movie: "Jaws"
- Good friend with : Otsuka Yuya, Tanaka Juri, Kikuchi Fuma
-  Juken no Kamisama (as Saionji Tadatsugu)
-  Battery (as Harada Seiha)
-  Koishite Akuma (as Miura Shota)
-  Hataraku Gon! (as Gondawara Haru)
-  Hidarime Tantei EYE (ep 4) (as Shimada)
-  Shiritsu Bakaleya Koukou
-  Great Teacher Onizuka
-  Kasuka na Kanojo
-  Bukatsu, Suki Janakya Dame Desu Ka?
-  Kansatsui Asagao
-  Kansatsui Asagao 2
-  Morimoto Keiji no Ojisan Kansatsu Nikki
-  Bushi-Stant Aisakakun
-  Snow Prince Kinjirareta Koi no Melody
-  Shiritsu Bakaleya Koukou: The Movie
-  Ninjani Sanjo! Mirai e no Tatakai
-  Ninja Drones? / Eiga Shonentachi
-  Shonentachi
-  Moeyo Ken
- Johnny’s Jr Channel
- The Shonen Club
- Yan Yan JUMP
- Ocha no mizu Hakase
- Johnny’s Jr dex
- Able (2021)
- Yakult (2020)
- Baskin Robbins (2013)
- 31 Ice Cream Baskin Robbin “GW31% Campaign” (2013)
- 31 Ice Cream Baskin Robbin “Happy 4 You Campaign” (2013)
- Lotte Choco Pie (2010-2019)
- I'M IN LOVE (Composición: Morimoto Shintaro Lyrics: DJ-SHU)