Fulham started the game in positive fashion but defensive errors, which have played a huge part in their relegation to the Championship, allowed Newcastle to score two goals within the space of two minutes.
Jonjo Shelvey, back in the Magpies' starting 11, fired a fantastic half-volley into the top-left corner in the ninth minute after getting on the end of Matt Ritchie's corner before Ayoze Perez poked home from four yards after Sergio Rico made a hash of saving Christian Atsu's shot.
The Cottagers struggled for clear-cut chances in the opening 45 minutes and Aleksandar Mitrovic's glancing header was the closest they came to grabbing a goal back before the break.
Into the second half, and Newcastle grabbed a third goal when Switzerland international Fabian Schar powered a header in from eight yards after finding himself unmarked in the penalty area for his fourth goal of the campaign.
Fulham did have the ball in the back of the net when Zambo Anguissa got the better of Martin Dubravka, but the offside flag wrongly went up against the midfielder and the goal was chalked off.
Venezuelan Salomon Rondon added a fourth in the 90th minute for the Magpies when he tucked home from a tight angle after his initial shot was poorly saved at the near post by Rico, who had a game to forget.