Lisa Marie Simpson is a character in the animated television series The Simpsons, voiced by Yeardley Smith. Matt Groening, the creator of the series, named her after his sister. She is the oldest daughter and middle child of Homer and Marge Simpson, and the sister of Bart and Maggie.

Lisa is an extremely intelligent 8 year old girl, one of the most intelligent characters on the show, with an I.Q. of either 156 or 159. She also plays the saxophone.