Roman Catholic Diocese of Calgary

The Roman Catholic Diocese of Calgary is a Catholic diocese in the province of Alberta, Canada. It covers the Calgary Region, southern Alberta, and part of the Alberta's Rockies region. It is a suffragan diocese of the Roman Catholic Archdiocese of Edmonton.

There are 82 parishes and missions in the diocese. The diocese's cathedral is St. Mary's Cathedral, in Calgary. The current bishop is Frederick Henry, who was appointed in 1998.