Jimmy Cox (July 28, 1882 – March 1925) was an American songwriter famous for his Depression-era hit "Nobody Knows You When You're Down and Out".
Bessie Smith made the song famous and it was later repopularized by Derek and the Dominos (featuring Eric Clapton) on the album Layla and Other Assorted Love Songs. It was reintroduced to a fresh generation of music fans when Clapton performed the song in his 1992 MTV Unplugged appearance, which was also released on the album Unplugged.
The song has been covered by a wide variety of artists, including Peter, Paul and Mary, The Chad Mitchell Trio, Otis Redding, Popa Chubby, The Allman Brothers Band, Rod Stewart, Janis Joplin, B.B. King, Nina Simone, Sam Cooke, Bobby Womack, Katie Melua and Steve Winwood with The Spencer Davis Group.