The Mills Blue Rhythm Band was an American big band active during the 1930s, originating from New York City. Formed in 1930 by drummer Willie Lynch as the Blue Rhythm Band, it briefly operated as the Coconut Grove Orchestra before Irving Mills became its manager in 1931, leading to its rebranding as the Mills Blue Rhythm Band. Throughout its existence, the band was known by various names, including the "Blue Rhythm Band," "Blue Ribbon Band," "Blue Rhythm Boys," and "The Blue Racketeers," among others.

The band was a fixture at Harlem's famed Cotton Club, often taking on less-desirable engagements while serving as deputies for the orchestras of Duke Ellington and Cab Calloway, both managed by Mills. Despite recording over 150 sides for numerous labels such as Brunswick, Columbia, and Victor, the band never achieved the prominence of its contemporaries, partly due to a lack of a single identifiable leader and Mills' positioning of the band as understudies.

The Mills Blue Rhythm Band featured a revolving door of talented musicians, including trumpeter Henry "Red" Allen and trombonist J.C. Higginbotham. Leadership stints were held by figures like Edgar Hayes and Earl Jackson before Lucky Millinder took over in 1934, bringing a dynamic presence to the group. The band disbanded in 1938, with Millinder later reforming his own orchestra in 1940. Irving Mills briefly revived the band's name for two recording sessions in 1947, with trumpeter Charlie Shavers as the only original member participating.