There were no immediate reports of injuries or damage. The US Geological Survey said the quake occurred about 49 kilometers south of the popular Dominican tourist town of Punta Cana at a depth of 38 kilometers.
The Caribbean region experiences small earthquakes daily that people do not feel, although earthquakes of greater magnitude sometimes occur.
This year, a magnitude-5.0 quake hit near St Kitts in April, while a 6.5-magnitude tremor struck near Barbados in February. A 6.4-magnitude quake jolted Puerto Rico in January. None of those earthquakes caused any injuries or significant damage.