Koki Uchiyama (内山 昂輝, Uchiyama Kōki, August 16, 1990) is a Japanese actor, voice actor (seiyū) and singer from Saitama Prefecture. He is affiliated with Himawari Theater Group. In 2011, he won Best Rookie Actor at the 5th Seiyū Awards, and in 2015, Best Voice Actor at the Tokyo Anime Awards.
- Title: Koki Uchiyama
- Popularity: 8.07
- Known For: Acting
- Birthday: 1990-08-16
- Place of Birth: Saitama Prefecture, Japan
- Homepage: https://profile.himawari.net/view/1559
- Also Known As: Утияма Коки, 内山昂輝, Koki Uchiyama, Kōki Uchiyama, 内山昂辉, Uchiyama Koki, Uchiyama Kōki, Kouki Uchiyama, Uchiyama Kouki, うちやま こうき, 우치야마 코우키