The church, with a rectangular plan, measures 8.39 m by 16.11 m externally. The wall face is laid with accurately squared blocks, with minimal mortar joints, unlike the other spaces in the architectural complex.
The original entrance is located to the south-west where it has been incorporated into the other buildings. The doorway is currently devoid of any decorative elements, but the overlying masonry curtain’s reparations with an ‘opera incerta’ device in contrast to the ‘opera regolare’ outline suggest that the doorway was surmounted by a semicircular prothyrum or lunate arch.
Beyond the door, one enters the narthex, tripartite by two arches resting on two half-pillars towards the entrance and on the opposite side on two pillars. The round arches with their slightly raised profile also reveal, in their perfect stereotomy of form, the same care taken with the wall face.
The reuse of the rooms for forestry and pastoral purposes led to the modification of the interior space, in particular by separating the narthex from the hall.
In the presbytery area, on the southern wall of the church, the entrance to the hypogeum opens up.
The ecclesiastical layout is typologically similar to bicellular churches with an axis dome, although a series of clues suggest the presence of a single domed cell in correspondence with the sanctuary and the descent to the grotto.
Some evident formal solutions such as the plan of the apse, the great attention paid to the stereotomy of forms, the bicellular layout, would place the church of St. Angelo around the mid-12th century.
Interesting comparisons can be made with the church of S. Valentino in Bitonto (11th century), the church of S. Rocco in Turi (12th century), the church of Ognissanti in Valenzano (1080) or the church of Santa Margherita in Bisceglie (1198).