The French winger has found it difficult to break his way back into the side at St James' Park following a hamstring injury in December.
"I have to say his condition has disappointed me this week and we will be working hard in the next few days to get him up to speed because he lacks a bit of fitness, for sure," Pardew told reporters.
"I just think it's something we need to push him on at. His upper body strength is there, but we want to work on his general fitness. I think that needs to improve."
Ben Arfa will be missing for the Magpies when they face Swansea City at the Liberty Stadium in the Premier League on Saturday.