"Mr. Lonely" is a song by Canadian singer Deborah Cox. It was written by Ahmad Russell, Christopher Jennings, Eric Johnson, Eric Jones, Takia Jennings, and Terry Johnson for her third studio album The Morning After (2002), with production helmed by Jennings and Johnson along with William Lockwood. The song, along with several remix versions, was released as the album's second single in fall 2002 and reached number one the US Billboard Dance Club Songs.