The current building, which is in Early English style, incorporates some material and fittings from an earlier church on the site, including the font and an 18th-century memorial in the porch.

[2] St Deiniol's Church is near the centre of Llanddaniel Fab, a village in the south of Anglesey, north Wales.

[3] The date of first construction of a Christian place of worship in the area is uncertain, but it is said by 19th-century writers that a son of St Deiniol (the first Bishop of Bangor) established a church here in 616.

Some parts of that structure may have been reused in the current church, as the 1937 survey by the Royal Commission on Ancient and Historical Monuments in Wales and Monmouthshire considered that sections of the walls of the nave may be from the older building.

[7][8] In 1833, the antiquarian Angharad Llwyd described the old church as "a very ancient and dilapidated structure", which had "some good specimens of the architecture of a very remote period".

[4] Writing in 1846, the clergyman and antiquarian Harry Longueville Jones described it as one "so much altered by successive reparations, that little of its original architectural character has been preserved".

[9] St Deiniol's is no longer in use; in 2006, a guide to the churches of Anglesey noted that no services had been held for a number of years, and added that ivy was growing across the building.

Rowlands, who wrote a history of Anglesey (Mona Antiqua Restaurata) in 1723, served as priest here and in nearby parishes from 1696 onwards.

[2][9] Each section is steeply gabled, with the west end terminating in a bellcote surmounted by a cross and containing a single bell.