|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) who portrayed Tsukasa Kadoya/Kamen Rider Decade in Kamen Rider Decade. He would later reprise the role in Kamen Rider Wizard, several films, and Kamen Rider Zi-O.
Outside of Decade, he is known for his portrayal of Jinga in Garo: Gold Storm - Sho and 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 continuity.
- 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.
- 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.
- Regarding his appearance on Kamen Rider Zi-O, Inoue announced on his YouTube channel that it would be his final reprisal of Tsukasa , though he eventually returned in 2021 for Rider Time: Zi-O VS Decade & Decade VS Zi-O.
- When Inoue was shown Kamen Rider Revi's and Vice's Megalodon Genome forms, his initial reaction was confusion and thinking they were a new form of Decade and DiEnd respectively that he wasn't told about before being informed they were new characters completely. Additionally, he had thought the designs were fan made and not something officially created.