The interior effect is rich with a ponderous architectural restoration style, good proportions, a large organ and a chancel well-filled with good-quality monuments. On the axis of the church are tower base, nave and chancel. There are two small chapels to the S, the E one now occupied by the organ. The N aisle functions with the nave, but has a N return as a quasi-transept. From the aisle there is a large passage-squint connecting to the chancel, and to the E of that a small vestry. The two S chapels, the porch and the tower base are vaulted, otherwise the church has C19 roofs.
The nave has braced collar-beam trusses with quatrefoil piercings. Two-light S window. The pulpit is at the left and there are three blocks of pews occupying the nave and N aisle. The arcade at left is accurately copied from Castlemartin Church, with two-order arches, the inner bearing on very heavy abaci on thin round columns with conical caps (but with plain corbels in place of the face-corbels which at Castlemartin carry the outer order of the arches). The base of the tower is a steep pointed stone vault and opens fully into the nave, apart from a low screen. The N aisle roof is of common rafters with collars, and turns 90 degrees to form a N gable. The passage squint contains a small N window with C20 stained glass, representing St. Christopher and St. Francis.
The chancel roof is of common rafters with collars and arch braces, giving a barrel-vault effect, contrasting with the nave roof. The floor is black and red quarry tiles. There is a step at the chancel arch and two to the sanctuary. Pine communion rails with a double gate; trefoil-pierced decorative stiffeners beneath. The altar stands forward from a carved limestone reredos, added subsequently to the main 1868 restoration, in Gothic detailing with a central shelf and aedicule for the cross with cinquefoil head and polished coloured marble colonnettes and flanking buttresses. The E window is of deteriorating stained glass, the inscription concealed by the reredos. At the S a pair of lancets. Organ, occupying the E of the two S chapels, by Peter Conacher, Huddersfield, 1908.
The porch is vaulted and has a diagonally-boarded inner door with a stoup recess at the right. Benches at E and W.
The font is a C12 square bowl, scalloped beneath, on a short round pillar with a moulded base and square pedestal.
The monuments are predominantly of the Allen family and dominate the interior. Many were re-fixed from the pre-restoration building. they include that to John Bartlett Allen d.1803 and Elizabeth d.1790, at N of chancel: sarcophagus style, white marble against black, with achievement, by William Williams, mason, of St Florence; to Gertrude, wife of J. S. Allen, d.1825, with eulogy, also at N of chancel: framed in a Regency style, with urn at top, by Henry Wood of Bristol. To the S of the chancel are a monument to J. H. Allen JP MP, d.1843, with eulogy, in a Gothic surround in high relief, and to S. P. Allen, d.1861, in a simpler Gothic style.
In the nave is a memorial in the form of a draped urn and plaque to Penelope Keates, d.1868, and William Keates, deputy inspector of hospitals at Dacca, d.1869.
Fixed to the E wall of the porch is a C8 or C9 incised stone, 1 m in length by 25 cm wide, with a four-arm cross within a circle, the downward arm slightly extended. This was found in the porch floor in 1915.