The church comprises a nave with a N aisle of the 12thc. and a S aisle with clerestorey ofc.1300, and a 12thc. chancel. There is also a two-part crypt, rectangular under the chancel, and octagonal under the nave, both Romanesque. The fabric is of red Kenilworth-type sandstone, unless otherwise stated. Romanesque sculpture is found in the N doorway, which was resetc.1350 and is now protected by a porch, in the windows of the chancel both inside and out; on the corbel tables and buttresses of the chancel; in the chancel arch and the N nave arcade, and in the crypt.

No church is referred to at DS, but Leland apparently (to be checked) stated that the Saxon Bishop, St Milred, was buried at Berkswell. The advowson descended with the manor.

As implied above, much restoration work has been carried out on the exterior, and around the chancel arch. The most interesting and untouched part is the crypt. Pevsner suggests that the octagonal chamber may be of late Anglo-Saxon origin, as at St Augustine's, Canterbury. In view of its resetting, the S doorway may be a composite.

An 18thc. oil painting, reproduced in the church guide, shows a Perpendicular window in the chancel in the position of window 4, the interior of which has been reformed. The remaining four windows are probably genuine.