Ikuko Tani is a highly respected Japanese actress and voice actress, born on April 9, 1939, in Tokyo, Japan. She is affiliated with the talent agency Mausu Promotion. Tani is a graduate of the Haikyōza Yōseijo, the training institute for the prominent theatre company Haikyōza, which launched her long and distinguished career that began in the 1960s.

Tani is best known for her signature role as Moominmamma in the various anime adaptations of the Moomin series, including Tanoshii Moomin Ikka, Tanoshii Moomin Ikka: Moomin Tani no Suisei, and Tanoshii Moomin Ikka: Bōken Nikki. This role has become one of the most defining parts of her career. Her voice is frequently cast for maternal, grandmotherly, and authoritative female characters across a wide range of anime.

Her extensive anime filmography includes many of the roles specified. In Mieruko-chan, she voices the character Godmother. In The Beast Player Erin, she plays Queen Shin. She appears as the Grand Councilwoman in the anime series Stitch to Suna no Wakusei and other Stitch! productions. In the film A Letter to Momo, she voices the role of Great Grandmother (Sae Sadahama). She also lends her voice to both characters Dunkelheit and Lumière in the film After School Midnighters. Her role as Masako in the film Re-Birthday (also known as Happy Birthday: Inochi Kagayaku Toki) is also documented. Further demonstrating her range, she has voiced Annie in Lucy-May of the Southern Rainbow, the Queen of Hearts and Jim's mother and an old woman in various Fairy Tale Special Selection entries, and Oba-chan in Takoyaki Mant-Man. In the long-running franchise Juuni Senshi Bakuretsu Eto Ranger, she played the villain Bagi.

Beyond these roles, Tani has voiced numerous other significant characters in major anime, including Chiyo in Naruto Shippuden, Tsubone in Hunter x Hunter (2011), Hisa in Demon Slayer: Kimetsu no Yaiba, Miranda Holbrooke in Little Witch Academia, and Lizzie Bareare in Overlord.

In addition to her work in anime, Tani is prolific in the field of dubbing foreign films and television series into Japanese. She is widely recognized as the long-term Japanese dubbing voice for actresses Maggie Smith (including Professor Minerva McGonagall in the Harry Potter film series) and Judi Dench. She also provides the Japanese voice for the character Patrick Star in the animated series SpongeBob SquarePants. Her voice acting is characterized by a warm, steady, and often wise quality, which has made her a beloved and enduring presence in the Japanese entertainment industry for over six decades.