CCTV and extra lighting has been put up around the Church of the Assumption in Magherafelt to deter vandalism.
The church is adjacent to a town centre car park off King Street which is often frequented in the evenings by young people involved in illegal drinking.
Damage has been caused to it on a number of occasions and the PSNI and Policing and Community Safety Partnership assisted with the deterents.
A police spokesperson asked parents to ensure they know of the whereabouts of their children.
They also pleaded with the public to report any suspicious behaviour to police.