Tibet's spiritual leader was made an honorary citizen of the Italian capital on Monday by the city's mayor, Gianni Alemanno. China has accused the Dalai Lama, 73, of being behind the violence that hit Tibet last March. Beijing says 19 people were killed and 623 injured in the unrest.
"We express strong dissatisfaction and firm opposition," Foreign Ministry spokeswoman Jiang Yu told a news conference on Tuesday.
Yu also called Tibet "a matter of sovereignty and the territorial integrity" of China.
However, Italy's Foreign Ministry has attempted to distance itself from the decision.
"The Ministry of Foreign Affairs has already explained several times to the Chinese ambassador to Italy that the mayors of Italian cities are autonomous and make decisions completely independent from [Italy's] government," a Foreign Ministry statement read.
It was also noted that the Italian government "supports the policy of a united China."
