An earthquake of magnitude 7 struck Qinghai, China, early on Saturday, the GFZ German Research Center for Geosciences (GFZ) said.
The quake was at a depth of 10 km (6.21 miles) , GFZ said.
A 6.1-magnitude earthquake struck the southwestern Chinese province of Yunnan late Friday, killing at least one person, local officials and seismologists said.
The US Geological Survey said the epicentre of the quake - which hit at 9.48 pm (1348 GMT) at a relatively shallow depth of 10 kilometres - was near the city of Dali, a popular tourist destination.
The initial magnitude of 6.0 was revised upwards.
At least one person was confirmed dead after the quake in the mountainous province, a truck driver who had been crushed by a falling rock, provincial officials said in a statement, adding that three more people had been buried under rubble.
Local media published videos showing ceiling lamps swinging and vases falling off shelves, as well as groups of people who had run outdoors after the quake.
The provincial government said some buildings had collapsed and others had been damaged, and that the "disaster situation was undergoing further verification."
The China Earthquake Networks Center (CENC) warned people to "stay away from buildings" in a post on the Twitter-like Weibo platform.
The quake monitor said the earthquake followed a series of smaller quakes less than an hour before.
Yunnan is acutely vulnerable to earthquakes. The region sees frequent seismic activity from the collision of the Indian and Eurasian tectonic plates, which form the vast Himalayan mountain range.
In October 2014, hundreds of people were injured and more than 100,000 displaced after a shallow 6.0-magnitude tremor hit Yunnan, close to China's borders with Myanmar and Laos.
China is regularly hit by earthquakes, especially in its mountainous western and southwestern regions where Yunnan lies.
A powerful 7.9-magnitude quake in southwest Sichuan province in 2008 left 87,000 people dead or missing.
In February 2003, a powerful 6.8-magnitude quake killed 268 people in Xinjiang and caused significant damage.