Fine interior with S end gallery, N end apsed sanctuary screened by 2 Roman Doric columns in antis. Cornice all around with deep cove to ceiling. Two plain plaster roundels to ceiling centre. E wall has vestry door towards left, large statue niche right of door. Dado rail each side up to niche and corresponding window opposite. The ornate Italian altar formerly in the sanctuary has been removed. S end bow-fronted gallery on Roman Doric columns and piers, front of 2-2-2 panels with fluted pilasters between. In apse 2 fine Arts and Crafts style stained glass windows to Elydyr Herbert killed 1917 and Ivor Herbert, Lord Treowen (d 1933), of SS Bernard and Francis. In S wall 5 windows with C17 and perhaps C16 continental stained glass, probably Rhineland or Flemish in origin, put in in later C19. First has 1659 date and has 8 small panels in grisaille and inscription ?K. Immendorpff. Second head of saint, probably St James, under canopy, 3rd has St John with dragon in chalice, 4th C17 scene of the Presentation, wood-engraving style with colour and gold grounds, 5th with a saint and Christ blessing above. Sixth window has C20 glass to Ladt Treowen (d 1939), Christ and St Teresa.
Plaques to J.A.E. Herbert (d 1895), Lt Col Bleiddian Herbert (d 1931), Sir John Arthur Herbert (d 1945), Governor of Bengal 1939-43, Cecile Herbert of Clytha (d 1941), Brig-Gen. E.A. Herbert of Moynes Court (d 1948), and Mrs Fflorens Roch (d 1969).
Vestry has small plaster cornice, wall cupboards each side of N window, and Swindow C20 stained glass of St David, made at Caldey Abbey, conventional C15 style. Entrance lobby has 6-panel door, stone flag floor and gallery stairs, with stick balusters and ramped rail. E side window has stained glass of St Michael, to Arthur Herbert d 1921. W wall alabaster war memorial plaque.