The dance duo's involvement in the movie, about a gang of South London teens who must defend their council estate from aliens, was confirmed by Scott Pilgrim Vs. The World director Edgar Wright.
"Heard some of Basement Jaxx's score for Joe Cornish's Attack The Block yesterday. Still humming it today," Wright revealed on his Twitter page.
Nick Frost, Jodie Whittaker and Luke Treadaway are among the cast for Attack The Block, due to open in UK cinemas on April 8.