Manohar Singh was a veteran actor of Indian cinema and Indian theatre who was famous for playing character roles in films such as Party (1984) and Daddy (1989). Singh was an active member of the Indian Theatre network and worked extensively in television as well.

Born in 1938 in Kwara, Himachal Pradesh, Manohar Singh began his professional life with Drama Division. In 1971, he graduated from the National School of Drama (NSD) and started directing plays with the NSD Repertory Company. His first play as a director was Qatl Ki Hawas (1971). Singh delivered many memorable performances in productions like Tughlaq and Barve. His other performances in theatre were in plays such as King Lear, Himmat Mai (Mother Courage) and The Threepenny Opera. 

In 1982, Singh received the Sangeet Natak Akademi Award for Acting (Hindi theatre). He went on to become a theatre director and also served as the chief of the National School of Drama Repertory Company, from 1976 to 1988. The NSD also kept up his legacy by naming a graduate award after him, 'Manohar Singh Smriti Puruskar', in 2003.

In 1977, Singh starred in Amrit Nahata's controversial political satire film, Kissa Kursi Ka (1977). The film was banned during the Emergency period and prints of the film were confiscated. The industry however appreciated the performances of the actors, including that of Singh. He also worked in other critically acclaimed films such as Damul (1985), Main Azaad Hoon (1989), and Ek Din Achanak (1989). Singh also worked in popular commercial films such as Chandni (1989), Lamhe (1991), Sadak (1991) and 1942: A Love Story (1993).

His last film was Everybody Says I'm Fine! in 2001.

Singh also made his mark in the field of television and appeared in many successful shows including  Dard, Mahayagya, Tere Mere Sapne and Pal Chhin.

He died of lung cancer in 2002, in his early 60s.