The US Geological Survey put the magnitude of the quake at 6.2.
It was centred on the small town of Murmuri in Ilam province.
Most of the injuries were not serious, according to the local governor's office and the Red Crescent.
Up to 70 per cent of the houses in the town were damaged, and power and water supplies were cut.
Residents left their homes in nearby towns, fearing aftershocks.
DPA