Sérénade mélancolique in B♭ minor for violin and orchestra, Op. 26 (Russian: Меланхолическая серенада), is a piece by Pyotr Ilyich Tchaikovsky that was written in February 1875. It was his first work for violin and orchestra and was written immediately after he completed his First Piano Concerto

Hungarian violinist Leopold Auer had been professor of violin at the Imperial Conservatory in St. Petersburg since 1868. Tchaikovsky was a professor at the Moscow Conservatory starting in 1866 and knew of Auer. He had seen him perform in public, having noted "the great expressivity, the thoughtful finesse and poetry of the interpretation" in an 1874 review of Auer's playing. They met in January 1875, when both attended a reception at the home of Nikolai Rubinstein. Some sources say Tchaikovsky then resolved to write a piece for him, with one source saying Auer commissioned it, resulting in Sérénade mélancolique. It was completed by the following month. Tchaikovsky mentioned it in a letter to his brother Modest in February, where he wrote: "I have finished my Piano Concerto, and have already written a violin piece I have promised to Auer."

The piece was dedicated to Auer upon its publication by P. Jurgenson in February 1876, but Auer did not premiere it. It was first performed by Adolph Brodsky in January of 1876, at the seventh symphony concert of the Russian Musical Society in Moscow.

Two years later, Tchaikovsky was offended by Auer's criticisms of, and refusal to perform, the Violin Concerto in D major written for him, and he withdrew the dedication from both the concerto and Sérénade mélancolique, although it was impossible to remove his name from the edition then being printed by Jurgenson.