His plays have included Rosalie Sings Alone (1985), If Betty Should Rise (1985), Touch (1986), The World We Live On Turns So That the Sun Appears to Rise (1987), Stay (1990), Mattachine (1991), Thieves in the Night (1992) and The Power of Invention. He received a special Dora Mavor Moore Award in 1986 for Touch. In 1992, Touch was included in Making Out, the first anthology of Canadian plays by gay writers, alongside works by Ken Garnhum, Sky Gilbert, Daniel MacIvor, Harry Rintoul and Colin Thomas.
After the mid-1990s, Demchuk stopped writing new plays, concentrating on his work at the Canadian Broadcasting Corporation and on writing scripts for radio, film and television. In 1999, he wrote the radio drama Alice in Cyberspace, a contemporary reworking of Alice in Wonderland which aired for ten episodes on CBC Radio's This Morning. His other radio dramas included Alaska, The Island of Dr. Moreau and The Winter Market. In June 2012, he became a contributing writer for the online magazine Torontoist.
The Bone Mother was published in 2017 by ChiZine Publications. It was the first horror-themed novel ever to receive a nomination for the Giller, an award more commonly associated with conventional literary fiction rather than genre fiction. The book was a shortlisted finalist for the 2018 amazon.ca First Novel Award.
- "Demchuk, David". Canadian Theatre Encyclopedia, March 26, 2009.
- "Winnipeg-born author on Giller Prize long list". CTV Winnipeg, September 18, 2017.
- "Trio of one-act plays doesn't add up to much". The Globe and Mail, August 16, 1985.
- "Powerful, well-acted drama gains little from new first act". Toronto Star, August 8, 1986.
- "Two plays provide exception to stock fare at Rhubarb '86". The Globe and Mail, February 24, 1986.
- "Fringe helped his Betty to rise again". Toronto Star, June 28, 1991.
- "Fistful of gems at new play fest". Toronto Star, July 19, 1992.
- "The dark is needed to appreciate the light". Toronto Star, August 12, 1989.
- "Dora smiles on Tarragon with record 17 nominations". The Globe and Mail, May 15, 1986.
- "Book symbolizes gays' advances". The Globe and Mail, June 4, 1992.
- "Whatever happened to that hot young playwright? David Demchuk has gone to CBC but one of his plays returns." Toronto Star, May 13, 1999.
- "Modern Alice". Calgary Herald, December 15, 1999.
- Torontoist (2012-06-20). "Home, a Toronto Indie Game That Will Mess With Your Head". Torontoist. Retrieved 2017-09-23.
- "Review: Jennifer Nansubuga Makumbi's Kintu, David Demchuk's The Bone Mother and Pierre-Luc Landry's Listening for Jupiter". The Globe and Mail, August 25, 2017.
- "Three first-time authors make Giller Prize longlist". The Globe and Mail, September 18, 2017.
- "Sharon Bala, Omar El Akkad among finalists for $40K Amazon.ca First Novel Award". CBC Books, April 28, 2018.