The Charles Rennie Mackintosh Society is a non-profit body established in 1973 to promote awareness of the work of Scottish architect and designer Charles Rennie Mackintosh. The Society has groups in Glasgow, Bath, London and Southeast England, North of England and Japan, and also in Port Vendres in North Catalonia, where Mackintosh spent the last four years of his life.

The aims of the Society are to support the conservation, preservation, maintenance and improvement of buildings and objects designed by Charles Rennie Mackintosh, his immediate circle of friends and collaborators - known as "The Four Macs": James Herbert McNair and the sisters Margaret and Frances Macdonald - and his contemporaries. It also aims to make Mackintosh's work known by publishing books, organising exhibitions and conferences and by carrying out important educational and public awareness work.

The Society also owns the Queen's Cross Church (1896-1899) in the suburb of Maryhill near the centre of Glasgow, the only religious building designed by Mackintosh. It is based on a Gothic style construction system and dominated by a powerful tower that seems to belong to a Norman castle.