St Mary's Church is a medieval church in the town of Llannerch-y-medd, Anglesey, Wales.

The east doorway in the tower and other parts of the tower probably date to the 12th century.

It was extensively rebuilt in 1850 by the architect Henry Kennedy of Bangor.

It was designated a Grade II-listed building on 5 December 1970.

[1] Media related to St Mary's Church, Llannerch-y-medd at Wikimedia Commons