The government of Yan'an, Shaanxi Province, reported that the fire broke out in the 16-storey World Trade Building in the city's downtown at about 4:30 am local time.
About 50 people staying at a hotel on the upper floors of the building were evacuated.
One of the security guards who helped in the evacuation is missing, state-run Xinhua news agency reported.
Sixteen people were taken to hospital suffering from carbon monoxide poisoning due to inhalation of smoke, but no one was in life-threatening danger, officials said.
More than 460 firemen and police brought the blaze under control after noon, officials added.
The cause of the fire is being investigated.