"I earnestly urge the Chinese authorities to exercise restraint in dealing with the situation in a spirit of understanding and far-sightedness," His Holiness said.
"I offer my prayers for those who lost their lives, their families and others affected by this sad turn of events," His Holiness added.
At least 156 people were killed in protests that started on Sunday evening in Urumqi, the capital city of Xinjiang Uighur Autonomous Region. More than 1,000 others were injured, Xinhua, China's official news agency reported.
However, Uighur groups put the death toll as high as 840. They also say that the majority of the dead were Uighurs.
The protests started when a group of protesters demanded an investigation into the death of two ethnic Uighurs who died during a fight with Han Chinese workers at a toy factory in late June, according to an IANS report.
Chinese President Hu Jintao earlier cut short his visit to Italy; where he was due to attend a G8 summit, "because of domestic affairs and the situation in Xinjiang".