|This article is about a/an actor in Kamen Rider Decade.|
Masahiro Inoue (井上 正大 Inoue Masahiro) is a Japanese actor and martial artist (Tae Kwon Do practitioner) best known for his role as Tsukasa Kadoya, the titular protagonist in Kamen Rider Decade. He would later reprise this role in Kamen Rider Wizard and Kamen Rider Zi-O.
He voiced Kamen Rider Decade in the video game Kamen Rider: Battride War.
Outside of Decade, he portrayed the villainous role of Jinga in Garo: Gold Storm - Sho and the good counterpart as the protagonist in Kami no Kiba: Jinga.
Inoue debuted as an actor in 2008, where he played Keigo Atobe in the Prince of Tennis musicals. One year later, he landed the lead role of Tsukasa in Kamen Rider Decade, where he would continue to play the role in several future crossovers of the character.
From 2015 to 2018, Inoue starred as Jinga in the Garo franchise, portraying the main antagonist in the Yami o Terasu Mono timeline.
- Cho Kamen Rider Den-O & Decade Neo Generations: The Onigashima Warship (2009) - Tsukasa Kadoya/Kamen Rider Decade
- Kamen Rider Decade: All Riders vs. Dai-Shocker (2009) - Tsukasa Kadoya/Kamen Rider Decade
- Kamen Rider × Kamen Rider W & Decade: Movie War 2010 (2009) - Tsukasa Kadoya/Kamen Rider Decade
- Kamen Rider × Super Sentai: Super Hero Taisen (2012) - Tsukasa Kadoya/Kamen Rider Decade
- Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai (2014) - Tsukasa Kadoya/Kamen Rider Decade
- Garo ~Kami no Kiba~ (2018) - Jinga
- Kamen Rider G (2009) - Kamen Rider Decade (voice only, 1 special)
- Kamen Rider Decade (2009) - Tsukasa Kadoya/Kamen Rider Decade (main)
- Samurai Sentai Shinkenger (2009) - Tsukasa Kadoya/Kamen Rider Decade (guest, 1 crossover episode)
- Kamen Rider Wizard (2013) - Tsukasa Kadoya/Kamen Rider Decade (guest, 2 episodes)
- Garo ~ Gold Storm: Sho ~ (2015) - Jinga (main)
- Fang of God: Jinga (2018) - Jinga Mikage/Rose, the Shining Shadow Knight (main)
- Kamen Rider Zi-O (2018-2019) - Tsukasa/Kadoya/Kamen Rider Decade (recurring, several episodes)
- Oronamin C - Kamen Rider Decade (voice only, 1 TV Commercial)
- Kamen Rider Battride War (2013) - Tsukasa Kadoya/Kamen Rider Decade
- Ride the Wind (2009, credited as Tsukasa Kadoya)
- As with Inoue's role as Jinga in Garo: Goldstorm - Sho, it would become a joke to say that he entered the "World of GARO" during talk shows. According to him, he signed a Decade KamenRide card for Garo director Keita Amamiya.
- In 2015, Inoue was among the fans whom played the arcade game Narerunda! Kamen Rider Drive, receiving a souvenir card depicting himself as Kamen Rider Drive.
- Inoue is a day older than Takeru Satoh.
- He announced his marriage to a Sailor Moon actress Jamie Natsuki on December 2016, with their first child was born in April 17, 2017. However they divorced on May 8, 2020, which was confirmed by Inoue himself on Twitter. 
- Inoue is also a skilled martial artist, trained in both taekwondo and Shorinji Kempo, and demonstrated his skills on the variety show VS ARASHI.
- He is first dan holder in taekwondo and he shows his skill in martial art in the film Taekwondo Damashii: Rebirth, in which he is one of the protagonists.
- Inoue can solve a Rubik's Cube in under 3 minutes, with his fastest record as 2 minutes and 22 seconds.
- Inoue announced on his YouTube channel that his appearance in Kamen Rider Zi-O will be the last time he will reprise his role as Tsukasa Kadoya.