Officials reported damage at buildings both in town and in rural Kermanshah, as well as to some roadways. The temblor also downed power lines and caused power outages into the night as temperatures hovered around 8C.
The quake struck just after 8pm in Iran, meaning most were still awake at the time and able to quickly flee.
The 6.3 earthquake had a depth of 10 kilometres, according to the US Geological Survey. Iran state TV gave the depth as 5 kilometres. Such shallow earthquakes have broader damage.
The earthquake was felt as far away as the Iraqi capital of Baghdad, about 175 kilometres southwest.
Iran is located on major seismic faults and experiences an earthquake per day on average. In 2003, a magnitude 6.6 earthquake flattened the historic city of Bam in southern Iran, killing 26,000 people.
Last year's earthquake near Sarpol-e Zahab, a predominantly Kurdish town, had a magnitude of 7.3 and injured more than 9000 people. The region, nestled in the Zagros Mountains, largely rebuilt in recent decades after Iran and Iraq's ruinous 1980s war, saw many buildings collapse or sustain major damage in the 2017 quake.
Sarpol-e Zahab, some 520 kilometres southwest of the Iranian capital of Tehran, suffered half of the 2017 earthquake's casualties.
- AP