The landslide occurred in Pengshui County on Friday morning on the outskirts of Chongqing municipality, when massive amounts of rocks and soil washed down a slope, burying more than 10 residential buildings, state broadcaster CCTV said.
Ten people were rescued but sent to the hospital, while more than 1100 people have been relocated.
Photos and Associated Press videos showed that one of the fallen rocks appeared larger than a multistorey building, with ruins scattered across the steep terrain.
One of the damaged buildings had its top part crushed and a car was seen half-buried near another building.
The landslide contained about 18,000 cubic metres of rocks and debris, and the largest single rock was 3000 cubic metres, Wang Chuanjun, head of Planning and Natural Resources in Pengshui County, told a news conference on Friday.
CCTV said persistent rain hit Pengshui from Friday night to Saturday morning and 19.2 centimetres was recorded at a weather station.
The unstable weather made the rescue operation more challenging, it said.
As the rain eased slightly, rescue teams entered the site to conduct on-the-ground inspections of the collapsed buildings and riverbank areas.
While rescue operations were being carried out on one side of the massive rocks, teams would later need to look beneath them, where they might risk injury if the boulders became unstable and slide, CCTV reported.
Once the search of the surrounding areas was complete, officers would drill into the boulders and fill the holes with explosives to break them apart, it said.
China's National Development and Reform Commission on Saturday allocated a relief fund of 30 million yuan ($A6.4 million) to support the restoration of infrastructure and public service facilities following the disaster.
The rain-triggered landslide occurred near a stretch of the Wujiang River, which cuts through karst mountains peppered with small towns and terraces.
Pengshui County is in the southeast part of Chongqing, bordering the provinces of Hubei and Guizhou.
with DPA
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