The fire broke out at around 4:20 am on the ground floor of the inpatient building at the city's No 2 People's Hospital at Huangshi city, local officials said.
One person was killed on the spot and another died after jumping off the building, state-run Xinhua news agency reported.
Two other patients in the intensive care unit died after getting transferred to a safe place, a police official said.
The rest of the patients are stable, he said.
Firefighters put out the fire at around 4:50 am, but more than 200 square metres of the ground floor hall were completely destroyed in the fire.