[2] The first Saint Mary's Church, Warwick is a substantial sandstone building, constructed 1863–1865 to designs of prominent Brisbane architect, Benjamin Backhouse.

Father McGinty who travelled from Ipswich, and this was celebrated at the Horse and Jockey Inn, Palmerin Street, where services for most other denominations were held at this time.

[1][3][4] Various people, including Michael Knole, William Cowper and Sarah Ransley acquired the various future church lots (Allotments 7-12 of Section 49) by Deed of Grant on 16 August 1860.

By September 1863, John Cani and James Quinn, the parish priest and Bishop of Brisbane respectively, became the registered owners of these allotments.

[1] The plan for the church was duly prepared by prominent Brisbane architect, Benjamin Backhouse, to the specifications that it was to be simple but tasteful, in the Gothic style and in stone or brick.

Benjamin Joseph Backhouse arrived in Brisbane in May 1861, and designed many buildings of architectural pretension in Queensland over the next six years, before he departed for New South Wales by 1868.

By 1867 a Catholic school, run by the Misses O'Mara until the arrival of the Sisters of Mercy in 1874, was established in the church by the next parish priest, Father O'Reilly.

[1] The church is of solid sandstone construction, and conforms to a cruciform plan, with nave extending to the east, transepts to the north and south and chancel to the west.

The corrugated iron roof is gabled and has overhanging eaves lined with wide timber beaded boarding which returns to the interior of the space.

Buttressing is formed by extensions of the faces of both the porch and main body of the church, this detail is repeated on the transepts and western end of the building.

[1] Above the porch is a rose window, of heavy tracery, with some early glass panels; above this is a ventilation opening in the form of a Latin Cross.

[1] The north and south, transverse elevation feature projecting side entrances and transepts, among regularly spaced single lancet window openings.

[1] The first St Mary's Church was listed on the Queensland Heritage Register on 21 October 1992 having satisfied the following criteria.

The building is a good example of masonry church design of mid nineteenth century Queensland, influenced by the English revival of early Gothic architecture.