The landslide from a mountain engulfed the village of Xinmo around 6:00am (local time), burying 46 homes in the remote mountainous area of north Sichuan province, near the region of Tibet.
President Xi Jinping urged on the rescue effort, but state broadcaster CCTV reported that by midday the only people rescued were a couple and their two-month-old baby.
Xinhua said the estimated number of missing was provided by local authorities.
The landslide also blocked a two-kilometre section of a river.
Wang Yongbo, a local rescue official, told state broadcaster CCTV that an estimated 3 million cubic metres of earth and rock had slid down the mountain.