The Senegalese striker has been linked with a move away in January due to a buy-out clause in his contract, but the Magpies boss is confident of retaining his services.
The Senegalese forward has a clause in his contract that would allow him to leave the Magpies should a 7 million pound bid for his services be tabled. Pardew believes the 27-year-old is likely to sign a new deal with the Tyneside outfit, though, should he remain beyond the end of the upcoming window.
"I think he will stay, but there's a possibility he could go because of the clause that's still in force," Pardew said. "Really and truly this window is the key, I think, because if Demba goes in this window, it will cause us a problem. We will either move Demba on or we will secure him in the summer. In the summer - I won't let it run until the summer. I'll do something about it."
Ba has 11 goals this Premier League campaign, which is just two behind league-leaders Michu and Robin van Persie.