The collection dates back to 1955, when Robert and Signe McMichael began to collect works from artists associated to the Group of Seven, exhibiting their works at their home in Kleinburg. In 1965, the McMichaels formally reached an agreement to donate their collection and their Kleinburg property to the Government of Ontario in order to establish an art museum. The institution was opened to the public as the McMichael Conservation Collection of Art in 1966. The museum was formally incorporated into the McMichael Canadian Art Collection in 1972. Although the museum was originally established with an institutional focus on the Group of Seven, the museum's mandate was later expanded to include contemporary Canadian art, and art from the different Indigenous groups in Canada.