The Gladstone is a theatre in Ottawa, Ontario, Canada offering live theatre produced by a partnership of independent professional theatre companies. It is located on Gladstone Avenue just west of Preston Street. It is the former home of the Great Canadian Theatre Company.
The building started out as a cinderblock garage. In 1982, Great Canadian Theatre Company converted it into a 230-seat theatre. In 2008, GCTC moved out into the Irving Greenberg Theatre Centre. At the end of the 2007 GCTC season, the building was purchased by Steve Martin and Marilisa Granzotto, owners of a nearby Arthur Murray Dance Studio, and renovated at an approximate cost of half a million CAD. In 2011, Plosive Productions and SevenThirty Productions joined forces to take on the operation of the theatre. The partnership expanded to include shows by Black Sheep Theatre, Bear and Co. and, in 2013, Same Day Theatre. 
The Gladstone Theatre is programmed by a partnership of independent theatre companies. For the 2013-14 season, those partners included Plosive Productions, SevenThirty Productions, Black Sheep Theatre, Bear & Co., and Same Day Theatre. The production companies are local to Ottawa.
- "Show will go on at former theatre company building". CBC News. August 2, 2007. Retrieved 2009-08-13.
- "Glamorous Gladstone theatre opens in Ottawa". CBC News. September 12, 2008. Retrieved 2009-08-13.