The epicenter of the quake that hit Zigui County was monitored at a depth of 5 kilometres, the Center said.
The earthquake came after a 4.3-magnitude tremor hit the same area on Thursday, which is about 30 km from the Three Gorges Dam, the country's largest multi-functional water control system.
Normal operation of the project was not affected after Thursday's quake, state-run Xinhua news agency reported.