Rescuers in Yunnan Province said on Friday night they had reached 90 percent of the six quake-hit counties under Zhaotong, where a total of 740,000 people had been affected by the quakes.
The disaster has so far incurred 3.5 billion yuan ($551 million) in direct economic losses, Yunnan's civil affairs department said.
Two quakes measuring 5.7 and 5.6 on the Richter scale hit a border area near Yiliang in Yunnan and Weining county in Guizhou province at 11:19 am and 12:16 pm Friday, respectively.
The quakes have cut off electricity and triggered landslides that have blocked roads, creating complications for rescuers.
Yunnan's civil affairs department said the quakes destroyed 6,650 houses and damaged 430,000 others. More than 100,000 residents have been evacuated and 100,000 others are in need of relocation.
Local authorities are also taking epidemic control measures after shed collapses had killed more than 4,300 heads of cattle in Yunnan. Over 153 hectares of farmlands were damaged or destroyed.
Officials in Guizhou said two people were injured and lives of nearly 28,000 people were disrupted in Weining county. Eighteen houses were toppled and more than 10,000 houses were damaged in the quakes.