The country estimates around 40 per cent of stolen goods taken out of Italy are pieces of religious art.
The Italian Bishops' Conference joined with the country's cultural ministry and police to create the new rules which include security measures at churches, chapels and convents.
That could mean religious buildings installing CCTV, reducing opening hours, replacing original art with copies and more inspections.
General Mariano Mossa, commander of the Carabinieri (Italian Police), said: "We have a duty to a precious artistic heritage that is centuries old and absolutely priceless."
Fresh guidelines were prompted by the theft of the Madonna with St John the Evangelist painting at a church in northern Italy.
It was worth around £5million but alarms failed to go off as the thieves fled.
Culture Minister Dario Franceschini said: "Abbeys, monasteries, basilicas, cathedrals are testament to the history of Christianity over two millennia.
"It is fundamental to counter theft and the international clandestine traffic of Italy's religious patrimony."