Gregory LeNoir "Gregg" Allman (born December 8, 1947) is an American rock and blues singer-songwriter, keyboardist, guitarist and a founding member, with his brother Duane, of The Allman Brothers Band.

In the early 1970s, the Allman Brothers Band enjoyed huge success: their live album At Fillmore East is widely regarded as one of the best live albums ever made, and a number of their signature songs were written by Gregg. While it was unusual at the time, the band was based in the Southeastern United States. "Southern rock," a term Gregg coined for their musical genre, is a fusion of rock, blues, and country.