Philip Chapman Lesh (born March 15, 1940) is an American musician and a founding member of the Grateful Dead, with whom he played bass guitar throughout their 30-year career.

After the band’s disbanding in 1995, Lesh continued the tradition of Grateful Dead family music with side project Phil Lesh and Friends, which paid homage to the Dead’s music by playing their originals, common covers, and the songs of the members of his band. Lesh operates a music venue called Terrapin Crossroads. He scaled back his touring regimen in 2014 but continues to perform with Phil Lesh & Friends at select venues. From 2009 to 2014, he performed in Furthur alongside former Grateful Dead bandmate Bob Weir.

Lesh was born in Berkeley, California, and started out as a violin player. While enrolled at Berkeley High School he switched to trumpet and participated in all of the school’s music-related extracurricular activities. Studying the instrument under Bob Hansen, conductor of the symphonic Golden Gate Park Band, he developed a keen interest in avant-garde classical music and free jazz. After attending San Francisco State University for a semester, Lesh was unable to secure a favorable position in the school’s band or orchestra and determined that he was not ready to pursue a higher education. Upon dropping out, he successfully auditioned for the renowned Sixth Army Band (then stationed at the Presidio of San Francisco) with the assistance of Hansen but was ultimately determined to be unfit for military service.