Hound Dog was first recorded by Big Mama Thornton in 1953 as a blues song.
Hound Dog by Elvis Presley
While in Las Vegas in 1956, Elvis Presley heard the song being performed by Freddie Bell and the Bellboys. This band's version was nearly a parody of Thornton's original lyrics. Presley recorded this version on July 2, 1956 at RCA's New York City studio, and introduced it on the Milton Berle Show on June 5, 1956. Hound Dog would be the b-side song of the Don't Be Cruel single released on July 13, 1956.
The single sold over 5 million copies in the United States on its first release. It was his best selling single.