The France international will have an operation on his damaged groin either later this week or at the beginning of next week after limping out of the 1-0 Barclays Premier League defeat by West Ham two weekends ago.
Pardew said: "He will definitely have an operation, and we think it's going to be on Friday or Monday, I'm not sure. That's a blow to us because he's a top player for us."
Cabaye will definitely miss the Europa League clash with Maritimo at St James' Park, and Pardew also has a doubt over striker Shola Ameobi.
He said: "The only one we are a little bit concerned about is Shola this morning. He's got a slight groin niggle, so we are going to have to see how he shapes up for tomorrow's game."