Mami Horikoshi is a Japanese voice actress born on June 9, 1960, in Fukushima Prefecture. She is a graduate of the Faculty of Literature at Meiji University, where she majored in theatre. Her career in the entertainment industry began in 1981 while she was still a university student, initially working as a reporter for the Fuji TV show Ogawa Hiroshi Show. She eventually transitioned to voice acting, a field in which she has been active since the 1980s.

Throughout her career, Horikoshi has been affiliated with several talent agencies, including Office Normel, Ishida Office, Production Baobab, and Ōsawa Office. In March 2016, she joined Aoni Production, where she continues to be based.

Horikoshi is highly regarded for her versatility and is particularly known for specializing in warm, maternal roles, often voicing mothers, grandmothers, and kind-hearted female characters. This niche has earned her affectionate nicknames from fans, such as universal mother voice actor and national mom. Her extensive filmography includes prominent roles in numerous long-running and beloved anime series. Some of her notable anime television roles include Trippy's Mom in the Shimajiro franchise, Ashibe's Mom in Boyfriend, Kasumi Grandma in Hanakappa, and various characters over more than three decades in Crayon Shin-chan. She has also lent her voice to many other popular series, such as Detective Conan, One Piece, Weiß Kreuz, Soreike! Anpanman, and Violet Evergarden. More recently, she was part of the cast for the 2025 anime I May Be a Guild Receptionist, But I'll Solo Any Boss to Clock Out on Time.

Beyond anime, Horikoshi is a prolific voice actress in the field of dubbing foreign films and television series. She has provided the Japanese voice for characters in numerous major Hollywood and international productions. Among her most recognized dubbing roles are Aunt Lucy in the Paddington film series, Bonnie's Mom in Toy Story 4, and various characters in films starring actresses like Melissa McCarthy. Her extensive dubbing credits also include Disney and Pixar films such as Cars 2 and Wreck-It Ralph, as well as live-action titles like Con Air, Spy, and the television series Once Upon a Time.

Her work also extends to video games, where she has voiced characters in franchises such as the Tales of series, including Tales of the Abyss and Tales of Rebirth, as well as Valkyrie Profile 2: Silmeria and Drag-On Dragoon. In addition to character roles, Horikoshi frequently works as a narrator for television programs and documentaries. She has also been involved in training new talent, serving as a lecturer at voice actor academies.