Gary Lo will be joining from Queensland Cup outfit PNG Hunters, along with his current club-mate Jason Tali.
Mark Mexico will be joining from NRL club the Cronulla Sharks, while Charlie Wabo joins from domestic PNG club Mendi Muruks.
Thunder coach Stanley Gene is delighted that four players from his homeland will be coming to England to test their arms.
“I know from my own playing days just how much rugby league talent we have back home in Papua New Guinea," said the former Hull KR star.
"Many of those guys go on to ply their trade at the top level in Australia but we want to give them an opportunity to develop here in the UK.
"The four guys we’re bringing in from PNG for next season are strong, fast and powerful players who will make a big impact on the league.
"We’ve done well to sign them and I’m looking forward to working with them all next season."
Thunder managing director Keith Christie hopes that the four players can pave a way for more talent from the Pacific to arrive in North East England.
"The beauty of having someone as high profile as Stan as our head coach is that we can attract some of the best international talents here to Thunder, something that will really help us make those next steps onwards towards where we want the club to be," he said.
"All four of the guys we’re bringing in are high profile signings and in the case of Gary Lo we’ve beaten off competition from NRL to bring him to Gateshead Thunder.
"We’re looking forward to welcoming these guys, and a number of others over the coming years to the region, and to building a little outpost of the Pacific here in Papua New Gateshead!"