"Soul Finger" is the first single released by R&B group the Bar-Kays. It was issued by Stax Records on the Volt Records label on April 14, 1967.

The song was written by the Bar-Kays while they were rehearsing with Norman West to perform a cover of J.J. Jackson's "But It's Alright". It begins with the melody of the popular children's song "Mary Had a Little Lamb" and then cuts into the main riff, punctuated with a high trumpet trill. It features a chorus of neighborhood children who had been loitering outside the recording studio; they were instructed to shout "Soul Finger!" and were paid with Coca-Cola. The idea for the title and the shouts came from the Stax songwriters Isaac Hayes and David Porter.

"Soul Finger" was a hit in the United States, peaking at number 3 on the U.S. Billboard R&B singles chart and number 17 on the Billboard Hot 100. The B-side of the single was "Knucklehead", written by Booker T. Jones and Steve Cropper, which reached number 28 on the R&B singles chart and number 76 on the Hot 100. "Soul Finger" and "Knucklehead" were the first two tracks of the Bar-Kays' first LP, Soul Finger, issued on July 10, after nine more tracks had been recorded on June 23.