"I'm an Old Cowhand (From the Rio Grande)" is a comic song written by Johnny Mercer for the Paramount Pictures release Rhythm on the Range and sung by its star, Bing Crosby. The Crosby commercial recording was made on July 17, 1936, with Jimmy Dorsey & his Orchestra for Decca Records. It was a huge hit in 1936, reaching the No. 2 spot in the charts of the day, and it greatly furthered Mercer's career. Crosby recorded the song again in 1954 for his album Bing: A Musical Autobiography. Members of the Western Writers of America chose it as one of the Top 100 Western songs of all time. It has also been covered by numerous jazz musicians, including Sonny Rollins, Monty Alexander, Joshua Redman, and John Scofield.

John Herndon Mercer was an American lyricist, songwriter, and singer, as well as a record label executive who co-founded Capitol Records with music industry businessmen Buddy DeSylva and Glenn E. Wallichs.