The song consists mainly of keyboards and drum machines, along with Prince's vocals. Two verses followed by chorusesform the main basis of the song. The song breaks down to an instrumental section with Prince repeating "I wanna fuck you" followed by him saying "Look, you Martian; I'm not saying this just to be nasty. I sincerely wanna fuck the taste out of your mouth." The final part of the song is an a cappella with Prince stating his philosophy on life—he loves God for fear of the afterlife but he's going to have fun while he can, a theme echoed in "1999". The song was performed live on the Purple Rain Tour.
The B-side, "Irresistible Bitch", received equal airplay and so qualified to chart alongside the A-side. The track was actually written and recorded in 1981, and segues from the song "Feel U Up", which was re-recorded in 1986 for theCamille project. The original version of "Irresistible Bitch" has a much rougher vocal, and is an organ-driven song. The 1983 remake has more percussion, both live drums and drum machines, along with bell-like keyboards and vocal backup from Wendy & Lisa. The lyrics are the familiar Prince theme of a jilted lover who treats his woman well, but gets treated badly in return. The song was performed on the Purple Rain tour, and once again with The New Power Generation, for their 1992–1993 tours.
Tina Turner has covered "Let's Pretend We're Married" in live performances, and one of these is included on her The Collected Recordings – Sixties to Nineties album. This performance was originally released as the B-side of her own "Show Some Respect" single in 1984 (in the UK, it was included as the B-side of "I Can't Stand the Rain" in 1985).
The band School of Fish covered the song on the B-side to their single "3 Strange Days".