A 5.1 magnitude earthquake struck the area between Iran's southern provinces of Bushehr and Fars late on Friday but no casualties were reported, the official IRNA news agency said.
The quake struck at 23:19 pm (18:49 GMT Friday) near the town of Dalaki in Bushehr province bordering Fars province.
The Fars news agency reported no casualties from Dalaki but said that people were in shock after the quake.
Iran, including the capital Tehran, sits astride several major fault lines in the earth's crust, and is prone to frequent quakes, many of which have been devastating.
The worst in recent times, of magnitude 6.3, hit the southern city of Bam in December 2003, killing 31,000 people -- about a quarter of its population -- and destroying the city's ancient mud-built citadel.