The earthquake hit at 03:36 GMT 32 kilometers (19.8 miles) northwest of Herat, the seismologists said, adding that the epicenter of the earthquake was at a depth of 10 kilometers.
No casualties and damages have been reported.
The area has been hit by several earthquakes in October. The death toll from the earthquakes in Herat has topped 2,400 people, the Afghan National Disasters Management Authority said. The UN Office for the Coordination of Humanitarian Affairs said that the earthquakes have affected at least 11,585 people.