Yumi Uchiyama is a Japanese voice actress born on October 30, 1987, in Tokyo, Japan. She is affiliated with the talent agency Office Osawa.

Uchiyama's interest in performing led her to enroll in the junior class of the Japan Narration Institute at the age of 15. She made her professional voice acting debut in 2005, providing voices for the television anime series Aria the Animation. However, shortly after beginning her career, she took a hiatus from voice acting for several years due to personal and family circumstances. She returned to the industry in 2010, landing her comeback role dubbing the character Abbey in the overseas drama Let's Love Vampire. The following year, in 2011, she secured her first major regular role as Nagisa Tennōji in the anime series A Channel, marking a significant step forward in her career resurgence.

For a period, Uchiyama was with the agency Arts Vision before transferring to her current agency, Office Osawa, in April 2017. On December 31, 2024, she announced her marriage to fellow voice actor Yusuke Kobayashi.

Uchiyama is recognized for her versatility, often playing both female and male characters, and is noted for her warm yet sometimes spirited vocal quality. Her career features a number of prominent and recurring roles across several major anime franchises. She is well-known for voicing the gentle and mysterious spirit Puck in the popular isekai series Re:Zero - Starting Life in Another World, a role she has played since 2016 across multiple seasons and related specials. She also provides the voice for the timid dark elf Mare Bello Fiore in the Overlord series, a character she has portrayed in its third, fourth seasons and various spin-offs. Demonstrating her range, she voices the protagonist Rudeus Greyrat, a character reincarnated as a young boy, in Mushoku Tensei: Jobless Reincarnation. Another significant and enduring role is that of Erika Chiba in The Irregular at Magic High School franchise, a character she has played in the main series, a film, and subsequent seasons.

Beyond these key roles, her extensive filmography includes voicing Candice Catnipp in Bleach: Thousand-Year Blood War, Fū Inubōzaki in the Yuki Yuna is a Hero series, Shun Kazami in various Bakugan anime, Ruri Miyamoto in Nisekoi, Arrow in Fire Force, and Momiji in Good Luck Girl!. Her work also extends to video games, where she has lent her voice to characters such as Ichiko Ohya in Persona 5, Cleo in Dragalia Lost, Natasha in Honkai: Star Rail, and Tangle the Lemur in the Sonic the Hedgehog series.