Perth County Conspiracy, also known as Perth County Conspiracy (does not exist) was a Canadian folk music group based in Stratford, Ontario. It was formed in 1969 and was active until at least 1977. The founding members were guitarist-singers Richard Keelan (formerly of the American band The Spike Drivers) and Cedric Smith, who were joined by Terry Jones (guitar, vocals), Michael Butler (bass) and George Taros (piano, vocals) and other friends and family members.

During the 1970s a number of others were a part of the Conspiracy such as David Woodhead, Jerome Jarvis, Larry Brown, Paul Gellman, Peter Cheyne and Dorit Learned. In the mid 1960s through to the late 1970s the Perth County Conspiracy would play nightly at the Black Swan Coffee House in Stratford, Ontario which was run by Harry Finlay. Guest performers at the Black Swan included such people as Brent Titcomb. The performances usually followed after the evening performances at the Stratford Shakespearean Festival Theatre. Oftentimes they would last till almost 4 a.m. In addition to playing at the Black Swan, the group also toured across Canada playing at many universities and also at Massey Hall.