"Mary Jane (All Night Long)" is a 1995 single by American R&B singer Mary J. Blige, taken from her second album, My Life. The song samples the Mary Jane Girls' "All Night Long" and Teddy Pendergrass' classic single "Close the Door". The official remix features LL Cool J.

The song hit #37 on the Hot R&B/Hip-Hop Airplay chart and was released as a single in the UK where it reached #17.