Sonja Stein is a German actress known for her work in voice acting, particularly for providing the German dubbing voices for characters in anime and animated series. One of her notable roles in anime is voicing the character Shiena Kenmochi in the German-language version of the series Riddle Story of Devil. In the series, Shiena Kenmochi is one of the twelve assassins in Class Black, a student and skilled hacker.

Beyond this role, Stein's voice acting work includes the character Cleo in the animated series H2O: Mermaid Adventures. Her performance credits are primarily in animation and family-oriented genres. In addition to animation, she has also appeared in live-action German television series, with roles in episodes of Notruf Hafenkante and Die Rosenheim-Cops.