In the worst-hit Shiqian county in Guizhou Province, six people were killed and another one is reportedly missing after torrential downpour lashed for two days.
Deluge hit 33 counties in Guizhou, affecting one million people, more than 80,000 of whom were evacuated.
More than 3,000 homes were damaged. Power, water and communication services were also affected due to the rains.
Thousands of tents, quilts and clothes have been sent to the affected areas, state-run Xinhua news agency reported.
In Sichuan Province, a 70-year-old villager in Tongjiang County, died after being hit by a mountain torrent on Monday.
At least 37 people died and six others remain unaccounted for in heavy floods last month.