The Regina Grey Nuns' Hospital was founded in 1907 by the Sisters of Charity (Grey Nuns) of St. Boniface, Manitoba. Reverend Sister Mary Duffin, foundress of the new mission in Regina, purchased the Park Sanatorium at 1400 Angus Street, previously owned and operated by Doctors D.S. Johnstone and J.A. Cullum. The School of Nursing was also opened during the inaugural year, with four students graduating in 1909. From 1910 to 1912, the Sisters constructed a new 50-bed hospital on two Dewdney Road lots provided by the City of Regina. The first Nurses' Home was built in 1915. Over the years many additions were made to the buildings, which grew to house the Saskatchewan Cancer Clinic and the Provincial Laboratories. In 1959 the first Medical Director was hired. By the Diamond Anniversary of the Hospital in 1967, bed capacity was at 520 and employees numbered 1076 (including student nurses).By the late 1960's, with the building in need of extensive renovations, the Sisters sought to withdraw from the ownership and management of the hospital. Mr. E. F. Bourassa, first lay Administrator of the Regina Grey Nuns' Hospital, proposed that it should become part of the South Saskatchewan Hospital Centre. The Sisters officially transferred ownership to the Saskatchewan Government on 31 August 1972, and the SSHC Board of Governors assumed control. The Regina Grey Nuns' Hospital was officially renamed Pasqua Hospital on 1 September 1973.

The following have served as Administrator: Eugene F. Bourassa (1967- 1970), Sister F. Dussault (Acting Administrator, 1971-1972).