The Vatican confirmed there was no casualty.
The Vatican Embassy in Damascus was hit by mortar fire on Tuesday but there were no casualties, a Vatican spokesman said.
It was not clear if the embassy was deliberately targeted.
It is located in the wealthy Maliki area of the Syrian capital, where there are several embassies as well as the residences of government and security officials.
“There was damage but no one was injured. The mortar hit a wing of the embassy that is currently not being used,” said Father Ciro Benedettini from the Vatican City.
An official at the embassy said the mortar had damaged part of the roof and left broken glass inside the building.
“It was very strong and noisy. We stayed inside and we were very afraid,” Monsignor Giorgio Chazza told Reuters in Beirut.
The embassy, which is still operating in the embattled city, had been hit eight to 10 times by mortar bombs since July, he said.
Rebels fighting to topple the government of President Bashar al-Assad regularly launch mortar fire at government-held areas inside Damascus.