Yūko Ōshima is a Japanese actress and former singer who has taken on a handful of voice roles in anime and animated films, though she is primarily known as a live-action performer and a former central member of the idol group AKB48.

Born on October 17, 1988, in Chiba, Japan, Ōshima began her entertainment career as a child actor in the late 1990s before rising to fame as a teenager in AKB48, where she became the captain of Team K and a consistent top vote-getter in the group's annual general elections. Following her graduation from AKB48 in 2014, she has continued to focus on her acting career in television and film.

As a voice actor, Ōshima is known for a few select roles. One of her earliest voice credits was in the 2007 original video anime project ICE, where she provided the voice for the character Rinne. In this post-apocalyptic science fiction story, she was one of several AKB48 members cast to voice main characters.

Earlier in her career, as a child actor, she appeared in the 1999 television mystery series Rasen, playing the dual role of Ami and Satomi. While this is a live-action role in a drama series, it is frequently listed alongside her voice work.

In the theatrical animated franchise Soreike! Anpanman, Ōshima voiced the character Mija. She played this guest role in the 2015 film Soreike! Anpanman: Mija to Mahō no Lamp, the twenty-seventh movie in the long-running children's series. The character Mija is a young magic-user who emerges from a mysterious lamp.