Jun Fukushima is a Japanese voice actor and narrator born on September 4, 1976, in Ehime Prefecture. He is affiliated with the talent agency Arts Vision and has been active in the industry since his debut in 1998. He is the eldest of three brothers. In addition to his performance work, Fukushima has also served as a lecturer at the Japan Narration Acting Institute, the training school he attended, where he has mentored aspiring voice actors.

Fukushima's early career consisted of numerous minor and supporting roles in anime series throughout the late 1990s and 2000s, such as in Offside, D.N.Angel, and Dear Boys, as well as appearances in long-running shows like Detective Conan. His profile began to rise in the 2010s. A significant turning point was his role as Yoshihisa Manabe in the 2013 series Kotoura-san, where his free-spirited performance during a live broadcast gained attention and showcased a different side of his personality compared to his previous serious roles. That same year, he also began voicing the energetic Osaka-born sprinter Shōkichi Naruko in the long-running sports anime Yowamushi Pedal, a role he has reprised across multiple sequels and specials, including Yowamushi Pedal Limit Break and Yowamushi Pedal: Special Ride.

Fukushima's career-defining role came in 2016 when he was cast as the protagonist Kazuma Satō in the comedy isekai series KonoSuba: God's Blessing on This Wonderful World!. His comedic timing and portrayal of the sarcastic, luckless adventurer earned him widespread acclaim and became his most iconic part. He has continued the role in subsequent seasons, including KonoSuba 3, the film Legend of Crimson, and the chibi-style crossover series Isekai Quartet and its related films. His work on KonoSuba also led to notable on-stage chemistry with co-star Rie Takahashi.

Following this success, Fukushima secured a variety of prominent roles, demonstrating a wide vocal range. He has voiced characters ranging from the comedic dragonoid Gabiru in That Time I Got Reincarnated as a Slime and its spin-off The Slime Diaries, to villains like Formaggio in JoJo's Bizarre Adventure: Golden Wind and Atrum Galliasta in Fate/stay night: Unlimited Blade Works. His other notable anime roles include Kosuke Inukai in the Science Fell in Love, So I Tried to Prove It series, M in Vivy -Fluorite Eye's Song-, Owner Kobayashi in Ya Boy Kongming!, Reiji Kirio in Drug Store in Another World, Makoto Takei in Fruits Basket 2nd Season, and Chikara Ōta in The Dangers in My Heart. He has also been a consistent presence in the Bakugan franchise, voicing Wynton Styles across multiple series including Bakugan: Evolutions, Bakugan: Geogan Rising, and Bakugan Battle Planet.

Beyond anime, Fukushima's voice work extends to video games, where he is known for roles such as Urashima Kotetsu in Touken Ranbu, Michalis in Fire Emblem Heroes, Vrtra in Final Fantasy XIV: Endwalker, and Kazuma Satō in the mobile game KonoSuba: Fantastic Days. He has also worked in live-action dubbing, providing the Japanese voice for the shinigami Ryuk in the 2015 television drama adaptation of Death Note.