Newcastle have already strengthened their defence with the signing of France defender Mathieu Debuchy from Lille but manager Alan Pardew is keen to bring in further reinforcements.
And it seems that Bong, who has been capped by Cameroon on 10 occasions, is also on the Magpies' radar.
Valenciennes president Jean-Raymond Legrand told le10sport.com: "Newcastle are very interested, they have made an offer.
"We will wait and see but I will not sell players unless I can replace them."
Asked if defence remained an area he was keen to address, Pardew said: "It's a position that we really need to strengthen, as we have let in some loose goals this year because we have not had the competition, and the likes of Davide Santon have needed a rest at times. That sort of pressure has told on us."
Following the departure of Demba Ba, Pardew is also in the market for a striker but confusion surrounds the future of long term target Loic Remy of Marseille.
Pardew said: "At the start of the window you get all sorts of mixed messages and it's very difficult to cement somebody down to a decision, because they're waiting to see if another club gets involved.
"But it will accelerate as we get nearer the end of the window. The problem for us teams who perhaps need to strengthen is trying to get those decisions made."