Alison Ahn is an American actress. She has appeared in TV series such as Billions, Orange Is the New Black, Raising Dion, and The Diplomat.

Ahn grew up in Pasadena, California. She is of Korean descent. She was involved in dance and theatre at college at Yale University, where she graduated in 2003. She received her MFA in acting from the California Institute of the Arts in 2006.

In New York theatre, Ahn made her Broadway debut in a short-lived revival of The Heidi Chronicles opposite Elisabeth Moss in February–May 2015. She starred off-Broadway in Rajiv Joseph's Letters of Suresh at the Tony Kiser Theatre in September–October 2021. A Times review said that her "messy charisma" elevated the play's letterwriting conceit.

In television, Ahn played recurring characters in series such as Billions (2016–2018) and Orange Is the New Black (2018). She played biotechnology company CEO Suzanne Wu on the Netflix superhero show Raising Dion (2019–2022), a role that was promoted to series regular in season two. She played another Netflix main role, Central Intelligence Agency (CIA) station chief Eidra Park, in the drama series The Diplomat (2023–present). She is set to appear in the Disney+ superhero show Agatha: Darkhold Diaries.

Ahn is in a relationship with actor William Jackson Harper, who co-starred with her in an outdoor production of Romeo + Juliet in New York in 2012.