"It's So Hard to Say Goodbye to Yesterday" is an R&B song written by Motown husband-and-wife songwriting team Freddie Perren and Christine Yarian for the 1975 film Cooley High.

The track was included on Boyz II Men's first album, Cooleyhighharmony, its name a reference to the film from which the song originated.

[citation needed] The song was used in the 1992 action film Lethal Weapon 3, in the funeral scene for Daryl, a 15-year-old gangbanger shot down by Murtaugh.

US cassette single Europe Maxi-CD The Flex covered "It's So Hard to Say Goodbye to Yesterday" for the House Party 2 soundtrack album, released in October 1991.

Latin pop group Barrio Boyzz performed the song acapella in Spanish at the Premio Lo Nuestro awards in May 1995 in honor of the late Tejano singer Selena, who was murdered two months prior.