The visitors had taken the lead after just four minutes through Kevin Maher, Dons hit back through Aaron Wilbraham only for Lee Hughes to strike back.
But Dons equalised seconds later through Jason Puncheon before taking over in the second half.
Sam Baldock capping off his best performance of the season with two well-taken goals before Alan Navarro added another. The rout was completed when substitute Ali Gerba tapped in from close range in added-on time.
It was a welcome win for Dons having drawn their last four and one that seriously dents the ambitions of Oldham.
It didn't look like it was going to be one of those days when Oldham took the lead from their first attack of the game though.
Navarro's poor pass let in Steve Kabba who ran at Miguel Llera, who made a perfectly clean challenge that somehow the referee deemed a foul on the edge of the box.
From the resulting free-kick Maher curled the ball over the wall and past the flat-footed Willy Gueret.
It immediately lifted the tempo of the game and Dons went looking for the equaliser straight away. Luke Chadwick threatened with a decent effort that Jan Budtz palmed away.
Then on the quarter hour Baldock got on the end of Wilbraham's flick after Dean Lewington hoofed clear, he raced past Sean Gregan and struck a left-foot shot that looked all the way in, but somehow hit the post and rebounded back to the keeper.
Dons kept on going though and did get the goal they deserved.
Lewington played a superb ball in for Baldock, who made a diagonal run across the centre-backs. His cross was a tad weak but it fell for Wilbraham who stole in just before the keeper to fire home his 14th of the season.
But the Dons fans were silenced again when Daniel Jones made a superb overlapping run and crossed the ball precisely for Hughes who got in the middle of Sean O'Hanlon and Llera to head home expertly.
Just 90 seconds later though Lewington sent a long ball upfield looking for the pace of Baldock, Budtz had to come and cleared with his head, but unfortunately for him it fell to a player with a wand of a left foot in Puncheon, who sent a lovely lob over the keeper to level the scores once more.
They could have even taken a lead into the break when Peter Leven finished a dazzling move with a low drive from the edge of the box that was saved by the legs of Budtz.
Dons started the second half brilliantly with Puncheon just flashing an effort past the post.
Then they took the lead when Baldock had too much pace for Gregan as he got on to Lewington's chip over the top, he cut across the defender and finished superbly.
Five minutes later Baldock scored again as Oldham were left stunned. Wilbraham knocked Lewington's cross back across goal for the striker who delicately sidefooted home.
Dons continued to boss the game, with Puncheon at times bamboozling the Latics with his skill on the ball.
Chances were coming with less frequency now though. Wilbraham, with a decent drive from the edge of the box, was one of the few to test Budtz.
Substitute Danny Whittaker had a tame shot from the edge of the area in return.
Dons then got a fifth with nine minutes left as sub Jemal Johnson's cross was only cleared as far as Navarro, who hit a low left-foot shot past Budtz, who despite getting a hand to the ball couldn't keep the ball out of the net.
The rout was completed when Lewington's cross found Gerba, who with a bizarre finish from close range hit the post only for it to rebound off his shins and find the net.