With more than 3,000 listed places of worship in Wales, the Welsh government said many were under threat.
New activities will be encouraged to save the buildings, either as religious centres or with an alternative purpose.
Deputy Culture Minister Ken Skates, visiting St Giles parish church in Wrexham, said it was "always a shame" to see "cherished buildings neglected".
The Grade I listed church hosts community groups and religious services, and received Welsh government funding to restore its tower.
An action plan has been launched to save historic religious buildings from neglect as their congregations dwindle.