Sena Koizumi is a Japanese voice actress born on September 3 and hailing from Aichi Prefecture. She is affiliated with the agency Arts Vision. Her career in voice acting began in the 2010s, having graduated from the Japan Narration Acting Institute. The film that inspired her to pursue voice acting was the Japanese dub of the movie Independence Day. Her first known anime role came in 2014 where she played a student in the series Love Live!.

Koizumi has built a steady career with a variety of supporting roles in long-running and popular anime series. She has had multiple guest roles in the long-running series Crayon Shin-chan from 2018 to 2024, playing characters such as a store clerk, a female university student, and a baby. She has also appeared in Doraemon playing a young girl and in the action anime Baki as a spectator. In the 2020s, her television credits include a high school girl in the music-themed comedy Paripi Komei and a small role in the idol drama Idolish7 Third Beat!.

One of her most prominent roles to date is in the theatrical film Pretty Guardian Sailor Moon Cosmos the Movie, released in 2023. In this two-part film, she voices the character Sailor Iron Mouse, a member of the antagonistic group Shadow Galactica. This role marked her as the new voice for the character in the franchise.

Beyond animation, Koizumi has contributed to numerous video games since 2015, including titles like Alteil Chronicle, Quiz RPG: The Magic and the Black Cat Wiz, and FOX-Flame Of Xenocide-. Her work also extends to dubbing foreign television series. She provided the Japanese voice for the character Ines Le Breton in the series Find Me in Paris. Additionally, she has worked as a narrator for television programs and has performed in audio dramas and audiobooks, showcasing her range as a performer.