The U.S. Geological Survey says the magnitude-7.5 quake hit about 89 kilometers (55 miles) southwest of Porgera early Monday in the Pacific island nation.
Geological Survey geophysicist Paul Caruso says the quake, which had a depth of 35 kilometers (22 miles), occurred in a rural, jungle area near a mountain range.
It wasn't immediately clear if there was damage. The Geological Survey website had 19 reports of people feeling the quake, including some saying the shaking was violent.
He says there is no tsunami danger.