A 3-1 win at The Valley should give them the opportunity of a top ten Premiership finish and they are still involved in the FA Cup and a quarter-final replay away to Middlesborough.
Newcastle's season effectively ended when they went out of the FA Cup to Chelsea in midweek and Alan Shearer's final season looks like ending in a whimper as the Geordies slipped to their third successive defeat after their recent revival under caretaker manager Glenn Roeder.
Considering both clubs had hard FA Cup matches in midweek they provided a good open game with Charlton deserving victory as a result of the better chances they created.
The home side went in front from the penalty spot after Jerome Thomas was fouled by Craig Moore and Darren Bent fired home from the spot to score his 15th Premiership goal and his 20th overall this season.
Had it not been for a fine save from Newcastle goalkeeper Shay Given earlier Bent would have put the home side in front, but the Irishman blocked the goalbound shot.
Newcastle equalised with a fantastic goal from former Charlton star Scott Parker who was booed by a section of the home crowd every time he touched the ball.
But he had the last laugh as he brought his side level with a superb 35-yard dipping effort which screamed into the net.
Within a minute Charlton had regained the lead with a fortuitous goal. Luke Young's free-kick was headed towards goal by Hermann Hreidarsson and Moore saw his clearance hit his fellow player Lee Bowyer, another former Charlton player, and ricochet into the net with the Newcastle midfielder unable to do anything about it.
Newcastle started brightly in the second half and England manager Sven-Goran Eriksson would have been pleased to see one of his injury-prone stars, Kieron Dyer, coming on for the second half.
Charlton were fortunate when Thomas Myhre could only push away Emre's shot and when Shearer returned the ball into the goalmouth, Chris Perry managed to scramble it clear.
Marcus Bent should have put the game beyond doubt for the home side when he beat the Newcastle offside trap, but with only Given to beat he dragged his shot wide of the post.
Charlton finally got their two-goal cushion when substitute Dennis Rommedahl skinned the Newcastle defence and crossed for another substitute, Jay Bothroyd, to head home with his first touch of the game.