By Agence France-Presse
The quake hit about 250 kilometres west of the town of Abepura in Papua province at 12:46 am local time, at a depth of 12 kilometres, according to the US Geological Survey.
The quake was felt weakly in Abepura, but most people did not notice it.
"I was still awake at home but I did not feel it all and none of my neighbors ran out of their home," Abepura resident Arul Firmansyah told AFP.
There were no immediate reports of casualties after the earthquake.
Indonesia experiences frequent seismic and volcanic activity due to its position on the Pacific "Ring of Fire", where tectonic plates collide.
Last year, a 7.5-magnitude quake and a subsequent tsunami in Palu on Sulawesi island killed more than 2,200 with a thousand more declared missing.
On December 26, 2004, a 9.1-magnitude earthquake struck Aceh province, causing a tsunami and killing more than 170,000.