It was recorded by the British Geological Survey at 4.16am on Thursday, about seven miles south of the village of Durness, in Sutherland.
Only one resident, who lives near Loch Eriboll, reported feeling a slight rumbling.
The earthquake is the largest recorded in the region since one on September 26, 1887, which had a magnitude of three. The Richter Magnitude Scale typically ranges from 0 to 9.
David Galloway, a seismologist at the British Geological Survey in Edinburgh, said the earthquake was fairly small and went relatively unnoticed by r esidents because of the time of day it happened.
"We only had one person, who was already awake, report to us that they felt a slight rumbling," he said.
"It is one of five or six recorded in the region within a 19-mile radius, and the largest since 1887. It is not a region that experiences many earthquakes."
No reports of any damage were made.