"Blue Lou" is a jazz standard from 1933, with music by Edgar Sampson and lyrics by Irving Mills. The copyright was registered in 1935 with the help of Mills's publishing company. The first recording was made by Benny Carter and His Orchestra on 16 October 1933, issued as a single on Okeh, coupled with "Lonesome Nights". Later recordings followed from Chick Webb in 1934 and Fletcher Henderson in 1936, and Charlie Shavers recorded a version in 1944 with Milt Hinton and J. C. Heard.
The tune makes strong use of the half-diminished chord, which some musicologists call the bebop chord. It became a staple of the swing era and has been recorded many times since, remaining part of the jazz repertoire.
