Substitute Dylan Davidson hit a goal of the season contender as Glentoran climbed to third place in the Dansk Bank Premiership table.
Ronnie McFall’s boys are now unbeaten since the opening day of the season and on this form are up with the big boys to stay.
First half goals from Curtis Allen and Robbie McDaid had Newry City on the ropes at the Oval.
Newry threatened to spoil the party by clawing a goal back through Conal Delaney, but strikes from Marcus Kane and Davidson eased the Glens over the finish line.
Glentoran boss Ronnie McFall made only one change to the team that draw at Glenavon last week, drafting in Connor Pepper, who served a two-game ban, for Joe Crowe.
City were missing their central defensive duo as John Boyle, scorer of his team’s winner against Cliftonville last time out, was attending a family wedding, while Darra Noonan failed a fitness test.
Marc McCabe was given a starting shirt in place of Stefan Lavery.
Before the game, Elliott Morris received a presentation to mark his 700th appearance from former Glens’ goalkeeper Alan Paterson.
But Morris almost blotted his copybook after only eight minutes when he totally misjudged a 25-yard drive from Stephen Hughes. The ball struck his leg and was looping towards the empty net, but the veteran shot stopper managed to get back to paw clear.
Even though the home team enjoyed a majority of possesion, they struggled to penetrate a stubborn City defence. McDaid tried his luck with a speculative shot from distance that flashed well over the crossbar.
But Allen had better luck on 29 minutes when he at last gave the home fans something to cheer.
John McGuigan’s delicious back-heel sent Allen clear in the left channel. Although he was confronted by goalkeeper Andy Coleman, the striker still managed to find the net from an awkward angle, the ball going in off the base of the post.
The Glens struck again in their very next attack. Allen was the provider this time. He gobbled up a great pass from skipper Marcus Kane before whipping in a delightful cross that was met by McDaid.
His initial effort crashed against a post, but he quickly rammed home the rebound.
After soaking up all the pressure in the first 45 minutes, City managed to haul themselves back into the game four minutes after the break.
Declan Carvill managed to get his head to a Mark Hughes corner kick to find the unmarked Delaney at the back post and he finished in style.
But normal service resumed on 60 minutes when Kane got up above everyone else the thump home a Ross Redman corner kick with the flick of his head.
Substitute Davidson then hit the goal of the game on 82 minutes, firing in a blistering drive from fully 40 yards.
To compound matters for Newry, Hughes missed a penalty with the last kick of the game, smashing the ball against the post.
GLENTORAN: Morris, Garrett (Davidson 80), Kane, Birney, Herron, Allen, McGuigan (McMahon 86), McDaid (Byrne 44), Pepper, Gordon, Redman.
Unused subs: Nelson, Crowe, Ferrin, McCarthy.
NEWRY CITY: Coleman, Mooney (Rushe 84), King, McCann (Walker 69), Carvill, McCabe, S Hughes, M Hughes, McCaul, Delaney (McArdle 69), Montgomery.
Unused subs: Maguire, Johnston, Teggart, Mullen.
REFEREE: Jamie Robinson.