The US Geological Survey says this morning's quake was centered roughly 8 kilometres east-southeast of San Pedro de Macoris, just east of the capital of Santo Domingo.
It occurred before dawn at a depth of about 100 kilometres.
Authorities say the quake was felt in parts of Santo Domingo and they fielded calls from some jittery residents.
The country is located near the intersection of the Caribbean and North American tectonic plants and small and moderate quakes are frequent.