Alexandra "Alex" Borstein (born February 15, 1971) is an American actress, singer, voice actress, writer, and comedian. She is best known for her long-running role as Lois Griffin in the animated television series Family Guy, as well as her work on the sketch comedy series MADtv.

A native of Highland Park, Illinois, Borstein graduated from San Francisco State University, where she studied rhetoric. She trained in improvisational comedy at the ACME Comedy Theatre near Hollywood, California, and was selected for MADtv after being spotted by talent scouts who noticed her work at the theatre. She was a writer and voice actress for several television shows, including Casper, The Pink Panther and the Brain, and Mighty Morphin Power Rangers: Zeo, before joining the cast of MADtv as a guest actress and later as a regular cast member in 1997.

As an actress, she has appeared in such films as Lizzie McGuire, Catwoman, and Dinner for Schmucks.