The quake was registered at 11:20 GMT. The epicentre of the earthquake was located 96 kilometres (60 miles) to the east of the town of Kimbe at a depth of 63 kilometres.
No casualties or damages have been reported.
READ MORE: Magnitude 7.7 Quake Hits Southeast of Ecuador — USGS
Earlier in February, another 6.4-magnitude quake was reported in New Ireland, Papua New Guinea.
Last year, three earthquakes measuring 5.7, 5.9 and 6.2 on the Richter magnitude scale struck Papua New Guinea following a powerful quake that hit the Pacific island nation, the United States Geological Survey (USGS) reported.