St Mary's Catholic Church is situated on a large corner block at the intersection of Merivale and Peel Streets in a light industrial and commercial area of the inner Brisbane suburb of South Brisbane.
An imposing rendered masonry building with corrugated iron roofs the church is located on the highest part of the site near the western corner.
The front of the church faces northwest onto Peel Street.
Formerly occupied by an earlier church, the northern portion of the site adjacent to the church and closest to the street intersection is now a car park with some landscaping.
In the eastern part of the site facing onto Merivale Street is the former presbytery, a timber building on stumps with corrugated iron hip roofs.
The former presbytery is not considered to be of cultural heritage significance.

St Mary's Catholic Church consists of a wide high central space or nave, narrower aisles on each side of the nave, and a semicircular chancel.
A proposed bell tower and transepts were never built.
The nave, a double height space with a clerestory, projects forward of the single storey side aisles to form the main facade or liturgical west front of the church.
Terminating the longitudinal axis of the nave at the liturgical eastern end is the projecting semicircular chancel.
Small rooms, the sacristy and vestry, flank the chancel on the north and south.
The nave is roofed by a simple timber framed gable roof with gabled ventilators and the aisles by lean-to roofs.
The chancel, sacristy and vestry, all additions at the rear of the church, have smaller separate roofs that are largely concealed by parapet walls.
The arrangement and form of the church is based on the traditional model of the basilica, originally a type of Roman public building that early Christians adapted for worship.

Described at the time of its completion as being built in a style of architecture based on early Italian, the church has a form and architectural features that are associated with the Romanesque revival but includes a variety of details drawn from other styles.
The most characteristic feature of Romanesque architecture is the use of the round arch.
Other distinguishing motifs that are used at St Mary's include the wheel or rose window, a frieze that contains a blind arcade, string courses and a type of arched corbel motif known as mock machicolation.

The liturgical west front of the church, which actually faces northwest, is simple in form but richly embellished with architectural detail.
A two storey structure, taller than it is wide, the symmetrical west front is divided into three bays and surmounted by a parapeted gable in the form of a broken bed pediment.
The central bay of the facade contains the main entrance to the church, an imposing arched opening with a shafted jamb framing a recessed doorway.
Over the timber panelled doors is a semicircular tympanum containing three arched windows and above the tympanum, a blind arcade of colonettes (thin columns).
The main feature of the gable is a wheel window centred in the gap created by the broken base of the pediment.
Raked corbelling over the wheel window supports the projecting edge of the pediment.
A cross is situated at the pinnacle of the pediment and at the other end of the ridge of the nave roof.

The bays on either side of the entrance bay consist of pairs of pilasters on a banded base that appear to support the pediment.
Between each set of pilasters are two narrow rectangular windows separated by a half or engaged column.
A small square window centred in the base of each bay has unusual moulded surrounds including jambs terminated by a stylised volute and a coved cornice with a leaf pattern.
Other facade details include rosettes, dogtooth banding, acanthus leaf capitals to pilasters and arabesque ornamentation on the pediment.

The northeast and southwest side elevations are similar.
The aisles consist of four bays delineated by engaged piers with an ornamental top.
Tall narrow windows with round arched tops are arranged in pairs in each bay with the exception of the bay second from the front th
St Mary's Catholic Church is situated on a large corner block at the intersection of Merivale and Peel Streets in a light industrial and commercial area of the inner Brisbane suburb of South Brisbane. An imposing rendered masonry building with corrugated iron roofs the church is located on the highest part of the site near the western corner. The front of the church faces northwest onto Peel Street. Formerly occupied by an earlier church, the northern portion of the site adjacent to the church and closest to the street intersection is now a car park with some landscaping. In the eastern part of the site facing onto Merivale Street is the former presbytery, a timber building on stumps with corrugated iron hip roofs. The former presbytery is not considered to be of cultural heritage significance.
St Mary's Catholic Church consists of a wide high central space or nave, narrower aisles on each side of the nave, and a semicircular chancel. A proposed bell tower and transepts were never built. The nave, a double height space with a clerestory, projects forward of the single storey side aisles to form the main facade or liturgical west front of the church. Terminating the longitudinal axis of the nave at the liturgical eastern end is the projecting semicircular chancel. Small rooms, the sacristy and vestry, flank the chancel on the north and south. The nave is roofed by a simple timber framed gable roof with gabled ventilators and the aisles by lean-to roofs. The chancel, sacristy and vestry, all additions at the rear of the church, have smaller separate roofs that are largely concealed by parapet walls. The arrangement and form of the church is based on the traditional model of the basilica, originally a type of Roman public building that early Christians adapted for worship.
Described at the time of its completion as being built in a style of architecture based on early Italian, the church has a form and architectural features that are associated with the Romanesque revival but includes a variety of details drawn from other styles. The most characteristic feature of Romanesque architecture is the use of the round arch. Other distinguishing motifs that are used at St Mary's include the wheel or rose window, a frieze that contains a blind arcade, string courses and a type of arched corbel motif known as mock machicolation.
The liturgical west front of the church, which actually faces northwest, is simple in form but richly embellished with architectural detail. A two storey structure, taller than it is wide, the symmetrical west front is divided into three bays and surmounted by a parapeted gable in the form of a broken bed pediment. The central bay of the facade contains the main entrance to the church, an imposing arched opening with a shafted jamb framing a recessed doorway. Over the timber panelled doors is a semicircular tympanum containing three arched windows and above the tympanum, a blind arcade of colonettes (thin columns). The main feature of the gable is a wheel window centred in the gap created by the broken base of the pediment. Raked corbelling over the wheel window supports the projecting edge of the pediment. A cross is situated at the pinnacle of the pediment and at the other end of the ridge of the nave roof.
The bays on either side of the entrance bay consist of pairs of pilasters on a banded base that appear to support the pediment. Between each set of pilasters are two narrow rectangular windows separated by a half or engaged column. A small square window centred in the base of each bay has unusual moulded surrounds including jambs terminated by a stylised volute and a coved cornice with a leaf pattern. Other facade details include rosettes, dogtooth banding, acanthus leaf capitals to pilasters and arabesque ornamentation on the pediment.
The northeast and southwest side elevations are similar. The aisles consist of four bays delineated by engaged piers with an ornamental top. Tall narrow windows with round arched tops are arranged in pairs in each bay with the exception of the bay second from the front th
St Mary's Church, South Brisbane