"The Lumberjack Song" is a comedy song by the comedy troupe Monty Python. The song was written and composed by Terry Jones, Michael Palin, and Fred Tomlinson.

It first appeared in the ninth episode of Monty Python's Flying Circus, "The Ant: An Introduction" on BBC1 on 14 December 1969. The song has since been performed in several forms, including film, stage, and LP, each time started from a different skit. At an NPR interview in 2007, Palin stated that the scene and the whole song were created in about 15 minutes, concluding a day's work, when the Python crew was stuck and unable to come up with a conclusion to the barbershop sketch that preceded it.

On 14 November 1975, "The Lumberjack Song" was released as a single in the UK, on Charisma Records, backed with "Spam Song". The A-side, produced by Python devotee George Harrison, was recorded at the Work House studio in London on 3 October 1975 and mixed at Harrison's Friar Park home the following day. A year later this single was reissued on 19 November 1976 as the first half of the double single release Python On Song. This version of the song has never been released on CD, although a remix containing alternate vocal takes from the session was included on the compilation album Monty Python Sings.