Billy Sheehan is an Irish American bassist known for his work with Talas, Steve Vai, David Lee Roth, Mr Big, and Niacin.

Sheehan has won Guitar Player Magazine's "Best Rock Bass Player" readers' poll five times for his "lead bass" playing style. Guitar Player has likened his soloing on the four-string instrument to Eddie Van Halen's on the six-string guitar. Sheehan's repertoire includes the use of chording, two-handed tapping and controlled feedback. However, Sheehan is also noted as a steady "true" bassist, fulfilling the traditional supportive role of the electric bass in the rock idiom.