The report says the quake struck early this morning in the town of Bastak, about 1,200 kilometres south of the capital, Tehran. It says many of the town buildings were damaged and that rescue workers were on the scene.
Iran sits on a series of seismic fault lines and experiences one slight quake a day on average.
In 2003, some 26,000 people were killed by a magnitude 6.6 quake that flattened the historic southeastern Iranian city of Bam.