The 7.1-magnitude quake struck the Tibetan Autonomous Prefecture of Yushu in southern Qinghai Province early on Wednesday, Apr 14.
According to rescue headquaters, it also toppled 15,000 residential buildings and forced 100,000 residents to be relocated.
"Freezing weather, high altitude and thin air have all made rescue efforts difficult," said Hou Shike, deputy head of the China International Search and Rescue Team.
"We have begun searching and rescue operation in Gyegu overnight, and will set up a field hospital today," he said.
Professional rescuers, soldiers, police officers and medical workers have been dispatched to Yushu from across the country.
Donations from governmental agencies, privately-run companies or individuals are also being rushed to the quake-hit region.