Gen Hoshino (星野 源, Hoshino Gen, born January 28, 1981) is a Japanese singer-songwriter, musician, actor, and writer.

Hoshino's movie debut, Lee Sang-il's 69, was an adaptation of the Ryū Murakami novel of the same name. He previously acted in various television dramas and stage plays. In 2012, he debuted as a voice actor, voicing Buddha in the original video animation (OVA) adaptation of Hikaru Nakamura's manga Saint Young Men, and also provided a theme song called "Gag" for its 2013 theatrical version, where he reprised his role. In 2013, he played the lead character in Masahide Ichii's Blindly in Love (箱入り息子の恋, Hakoiri Musuko no Koi) alongside Kaho, and starred in the Sion Sono film Why Don't You Play in Hell?. In 2016, Hoshino starred in TBS's The Full-Time Wife Escapist. With Yui Aragaki as his co-star, he portrayed a salaryman named Hiramasa Tsuzaki. The drama achieved steadily rising ratings, with a real-time viewership peak rating of 20.8% on the final episode, and an overall rating of 14.5%. Hoshino's performance earned him several Best Supporting Actor awards. He also provided the theme song for the drama, titled "Koi".