Prime Minister Calin Popescu Tariceanu requested an audience with the pontiff, meeting for about 10 minutes with Benedict at the end of his general audience, said the Rev. Federico Lombardi, the Vatican spokesman.
Tariceanu thanked the pontiff and the Catholic Church as a whole "for what they do to support immigrants and teach sentiments of tolerance and integration," Lombardi said.
Italy last week began deporting Romanians deemed to be a danger to public safety after a wave of violent crimes blamed on immigrants from Romania, one of the European Union's newest and poorest members.
The government adopted the emergency decree after a Romanian was arrested in connection with the beating death of the wife of an Italian naval commander in Rome's outskirts.
During his weekly Sunday blessing, Benedict reminded authorities that immigrants have obligations - and rights. "Those who deal with security and welcoming programs know how to use instruments aimed at guaranteeing the rights and duties that are at the foundations" of coexistence, he said.
Tariceanu came to Italy to hold talks with Italian Premier Romano Prodi, saying before he left Bucharest on Wednesday that he would ask Italian authorities to "ensure safety for the Romanians who work and lead an honest life in Italy and who represent the vast majority of Romanians there."
There are about 560,000 Romanians living in Italy, roughly 1 percent of the country's population. Many came after Romania joined the European Union on Jan. 1, taking jobs as bricklayers, maids, nannies, waiters and janitors.
"The crimes committed by Romanians have created a powerful emotion in Italy and lead to political statements which have sparked a wave of xenophobia that is very worrying," Tariceanu said.
Romania has warned against xenophobia after a mob of eight to 10 people wielding knives and metal bars set upon a handful of Romanians in a Rome parking lot Friday night and wounded three of them - one seriously.
Italian authorities say statistics show foreigners commit a disproportionate number of crimes in Italy, and Rome Mayor Walter Veltroni said 75 percent of arrests in the city in the last year involved Romanians.