About 900 people were evacuated, and four were pulled from rubble with minor or no injuries, the local government said. No fatalities have been reported.
Shenzhen's fire brigade said it was working to free other trapped people - state media say 59 remain missing.
Two workers' dormitories are among the affected buildings.
The city is one of China's biggest and is a major industrial centre.
State media quoted officials as saying 36 men and 23 women were missing and that "signs of life" had been detected at three separate locations.
An area of 20,000 sq m (24,000 square yards) was covered with soil, the Public Security Bureau's firefighting bureau said.
The state-run Xinhua news agency quoted a local worker as saying he saw "red earth and mud running towards the company building".
Another resident living around 4km (2.5 miles) from the site described hearing a "loud explosion" at around noon as the landslide hit.
Ren Jiguang, the deputy chief of Shenzhen's public security bureau, told state broadcaster CCTV that most people had been moved to safety before the landslide hit.
Some 1,500 firefighters are at the scene, the Guangming New Area Government said on its official page on the Sina Weibo micro-blogging site.
Local media reported that the soil that came loose had been dug up in the past two years in construction work and was piled up nearby.
A statement on Weibo from the Shenzhen municipal government said the landslide had also triggered an explosion at a nearby gas station.
A landslide in the country's Zhejiang province in November killed at least 25 people.
Dozens of people are missing after a landslide engulfed 22 buildings at an industrial park in the southern Chinese city of Shenzhen.