Seishiro Kato (加藤 清史郎, Katō Seishirō, born August 4, 2001 in Kanagawa Prefecture) is a Japanese actor.

He debuted when he was 13 months old. He became recognized after his breakthrough role as Higuchi Yoroku (childhood name of Naoe Kanetsugu, as well as Kanetsugu's first son, Takematsu) in Tenchijin the 2009 edition of NHK Taiga Drama. Currently, he is actively appearing in many TV dramas, films, and TV commercials. He will also release a music CD titled Katsuobushi dayo Jinsei wa (かつおぶしだよ人生は, lit. "Life is Like a Dried Bonito") on September 2, 2009.^[1]

Filmography

Films

• The Boy Who Became a Star (星になった少年, Hoshi ni Natta Shōnen) (2005)
• I Won't Cry (なくもんか, Nakumon ka) (2009)
• Zatoichi (2010)
• You are Umasou (film) (2010)
• Ninja Kids!!! (2011) (Rantarō)
• Assassination Classroom: Graduation (2016) as Itona Horibe^[2]
• Hakubo (2019) as Yūsuke (voice)
• #HandballStrive (2020)
• The Sun Stands Still (2021) as Yūji Yanagi
• We're Millennials. Got a Problem?: The Movie (2023) as Hirata^[3]

Japanese dubbing of non-Japanese films

• Happy Feet - as Mumble (childhood)
• The Legend - as Ajik
• Where the Wild Things Are - as Max^[4]

TV dramas

• My Magician (ぼくの魔法使い, Boku no Mahō Tsukai) final episode (2003 NTV) - as Mini Mittan
• Manhattan Love Story (マンハッタンラブストーリー, Manhattan Rabu Sutōrī) 4th, 5th, & 10th episodes (2003, TBS) - as Yūya Doigaki
• Batsu Kare (バツ彼) 3rd & 8th episode (2004, TBS) - as Yūichi Yamane
• Sukiyaki - Kyu Sakamoto Story (上を向いて歩こう〜坂本九物語〜, Ue o Muite Arukō - Sakamoto Kyū Monogatari) (2005, TV Tokyo)
• Boogie-woogie of Love and Friendship (愛と友情のブギウギ, Ai to Yūjō no Bugi-ugi) (2005, NHK General) - as Daichi Ōtsuki
• Ultraman Mebius (ウルトラマンメビウス, Urutoraman Mebiusu) 24th episode (September 16, 2006 CBC)
• Yumeji Night Shakespeare Drama Special "Romeo and Juliet" (夢二夜シェイクスピア・ドラマスペシャル「ロミオとジュリエット」, Yumeji-ya Sheikusupia Dorama Supesharu "Romio to Jurietto") (April 7, 2007 NTV)
• The Summer You Gave Me - You Can Be Happy, If You Try Hard (君がくれた夏 〜がんばれば、幸せになれるよ〜, Kimi ga Kureta Batsu - Ganbareba Shiawase ni Nareru yo) (2007, NTV) - as Ryōya Kizaki
• Fūrin Kazan (風林火山) 9th, 11th, 13th, 15th, and 17th episodes (2007 NHK General, Taiga Drama - as Takeda Tarō (childhood name of Takeda Yoshinobu)
• Five (ファイブ, Faibu) (January 5, 2008, NHK General) - as Kenta Sayama
• Saito-san (斉藤さん, Saitō-san) (2008, NTV) - as Makoto Nakamura
• Ai no Gekijō - Straight to Remarriage! (愛の劇場 再婚一直線!, Ai no Gekijō - Saikon Icchokusen!) (2008 TBS) - as Manabu
• Kaidan Shin Mimibukuro Special "Gii" (怪談新耳袋スペシャル「ぎぃ」) (July 6, 2008, BS-i) - as Takeshi Toyama
• Ai no Gekijō - We Love Quintuplets! 2008 (愛の劇場 大好き! 五つ子 2008, Ai no Gekijō - Daisuki! Itsutsugo 2008) 7th episode (2008, TBS) - as Hiroshi Koizumi
• Thanks, Mom (ありがとう、オカン, Arigatō, Okan) (October 7, 2008 Fuji TV) - as Atsushi Irie
• Oh! My Girl!! (オー! マイ・ガール!!, Ō! Mai Gāru!!) (2008, NTV) - as Nozomu Yasuno
• Tenchijin (天地人) (2009 NHK Taiga Drama) - 1st & 2nd episodes as Higuchi Yoroku, 23rd episode as Naoe Takematsu
• Voice-voices of People Lost (ヴォイス〜命なき者の声〜, Voisu-Inochi Naki Mono no Koe) 1st and final episodes (January 12 and March 23, 2009 Fuji TV) - as childhood Daiki Kaji
• Uta no Oniisan (歌のおにいさん) 1st, 7th and final episodes (January 16, March 6 and 13, 2009 TV Asahi) - as Yōshichi
• Tōkyō Shōjo Mano Erina (東京少女真野恵里菜) 4th episode (February 28, 2009, BS-i) - as Kōhei Yokoyama
• Ninkyō Helper (任侠ヘルパー, Ninkyō Herupā) (2009 Fuji TV) - as Ryōta Hatori
• Yamato Nadeshiko Shichi Henge (ヤマトナデシコ七変化) (2010, TBS) - as Nakahara Takeru
• Jūichi-nin mo Iru! (11人もいる!) (2011, TV Asahi)
• Honjitsu wa Taian nari (本日は大安なり) (2012, NHK)
• Kirin ga Kuru (2020, NHK) - as Prince Sanehito

Theatre

• Les Misérables - Gavroche (2011-2013)
• Elisabeth - Young Rudolf (2012)
• Madama Butterfly - Dolore (2014)
• Love Never Dies - Gustave (2014)
• Kid Victory - Luke (2019)
• Newsies - Davey Jacobs (2020-2021)
• Be More Chill - Michael Mell (2022)