Sammie "Big Sam" Williams is an American trombonist and band leader from New Orleans, Louisiana.

He has been a member of the Dirty Dozen Brass Band and leads Big Sam's Funky Nation.

In his teens, Williams was a founding member of the Stooges Brass Band and joined the Dirty Dozen, allowing him to play with Karl Denson, Dave Matthews, Widespread Panic, and James Brown.

Big Sam's Funky Nation became his main band, which performed at Bonnaroo, Gathering of the Vibes, New Orleans Jazz & Heritage Festival, Voodoo Music Experience, South By Southwest, and on the television show Austin City Limits.

Williams is interviewed on screen and appears in performance footage in the 2005 documentary film Make It Funky!, which presents a history of New Orleans music and its influence on rhythm and blues, rock and roll, funk and jazz.