Jiuzhaigou, in southwestern Sichuan province, is famous for its fairyland landscape with blue, green and purple pools, snow-capped peaks, lakes and multi-tiered waterfalls.
State broadcaster CCTV said some of the key tourist sites had been closed and stranded tourists were being safely evacuated on Monday.
The closures come as China issued its highest alert for flash-floods across multiple provinces after Typhoon Noul, the strongest typhoon to hit the country in 2026, brought widespread torrential rains across southern and central regions.
"Due to mudslides, starting July 27, the area above Arrow Bamboo Lake (including Arrow Bamboo Lake) in Rize Valley and the entire Zechawa Valley in Jiuzhaigou Scenic Area will be temporarily closed to tourists," local authorities said.
China's Ministry of Water Resources and the China Meteorological Administration jointly issued a red warning for flash floods from Sunday night through Monday, warning of high risks in parts of Jiangxi, Hunan, Guangdong, Sichuan, Shaanxi, Gansu and southeastern Xinjiang.
Mudslides and soil erosion are common in China's mountainous regions, particularly where steep river valleys intersect, especially during the peak summer rainy season.
At least four deadly landslides have occurred across China in July.
In the southwestern city of Chongqing, a massive landslide following torrential rain killed 11 people, with 50 others still missing.
At least 21 people died after a landslide struck Tanchang, a mountainous county in the northwestern province of Gansu, while flash floods at a scenic camping spot in Gansu's Weiyuan county killed 10 tourists and injured 23 others.
In a separate disaster, five people were killed after a loess soil collapse buried a house in a village in northern Shanxi province.
The severe weather coincides with China entering its peak flood control window — known as Qixia Bashang — from mid-July to mid-August.
Weather experts warn extreme rainfall will increase in frequency and intensity over the coming weeks, with much of northern China set to experience 20 per cent to 50 per cent more precipitation than usual.