Goals from Emmanuel Adebayor, Mathieu Flamini and Cesc Fabregas served to see off a limp Kevin Keegan side.
The opening 15 minutes were a cagey affair with Arsenal full of running but all too often the final pass didn't find its target.
Arsenal's first real effort on goal came on 16 minutes when Abou Diaby dipped to meet Alex Hleb's cross from the right but his header flew high over the bar.
The Gunners would have taken the lead on 29 minutes had it not been for a timely interception from Stephen Carr to cut out Bacary Sagna's cross from the right before it was met by Eduardo, who was sliding in to redirect the ball past Shay Given.
The Gunners were denied a penalty a minute later when Claudio Cacapa appeared to cut out Adebayor's cross with his arm.
The appeals were waved away by referee Mike Riley and his assistant, who was just yards away.
Adebayor went close on 39 minutes with a spectacular full-blooded volley from Flamini's pass, but the Togo striker went for power when a little more emphasis on accuracy would have been the better option.
But he made amends just two minutes later when, again from an inch-perfect Flamini cross, he got in front of his marker to head past Given from just three yards out.
Newcastle came out for the second half with more purpose but their urgency was soon lost as Arsenal, for their part, looked to have at least another goal in them.
Diaby was wide with a shot and Flamini had an effort from the edge of the box comfortably saved on 68 minutes.
Arsene Wenger brought on Nicklas Bendtner on 71 minutes to play alongside Adebayor and within seconds of the change the Gunners were 2-0 up through Flamini.
The Frenchman, who has been one of Arsenal's best players this season, hit a thunderous 20-yard drive that winged its way into the top right corner of the net.
Keegan threw on Shola Ameobi to play up top alongside a very quiet Michael Owen, with Alan Smith operating behind the pair.
But the three points were secured in the 80th minute when Bendtner controlled a long free-kick into the Newcastle area before teeing up Fabregas to shoot past a stranded Given.
The Spaniard will have been disappointed with his effort six minutes earlier though when he blazed his shot over the bar from inside the area when Hleb had set him up with the goal begging to be breached.
Manuel Almunia was forced into his first save of the game in the 88th minute when he got a finger-tip to a Nicky Butt free-kick to parry the ball on to the bar.
Then within two minutes he was called into action again, getting down well to deny Ameobi as the visitors ended with a flourish.