The shallow quake struck 10km southeast of Norcia, a town in the province of Perugia, at around 3.30 am (01:30 GMT) according to the USGS.
USGS’s PAGER system, which predicts the impact of earthquakes, has issued a red alert - suggesting significant casualties and damage based on previous quake data.
A resident of the Rieti region, which is between Rome and the epicentre of the quake, told the Rainews24 channel that she and most of her neighbours had come out onto the street after feeling "very strong shaking".
In 2009 a 6.3-magnitude earthquake in the Aquila region, which was also felt in the Italian capital, left more than 300 dead.
Italy is often shaken by earthquakes. Another quake hit the northern Emilia Romagna region in May 2012, when two violent shocks 10 days apart left 23 people dead and 14,000 others homeless.