Latics got off to a good start as Ryan McLaughlin’s cross was deflected into his own net by Fleetwood Town defender Nathan Pond.
John Sheridan’s men continued to put the pressure on the Cod Army and they were rewarded with a second goal on 55 minutes.
Lee Erwin spun in the penalty area and volleyed past Alex Cairns to secure the convincing win and also record Connor Ripley’s 16th clean sheet in the league, two off the record.
Sheridan made one change from last weekend’s game against Southend United.
Tope Obadeyi was replaced by Aaron Amadi-Holloway who recovered from an injury which had kept him out since the Peterborough United clash.
It was a slow start to the game but it was Athletic who had the first opportunity of the game.
Ollie Banks’ corner found Anthony Gerrard in the box, he laid it back to Peter Clarke to strike but it deflected wide.
Chances for both sides followed as Erwin forced a good save from Cairns whilst Ripley denied David Ball from 12 yards.
Erwin will wonder how he didn’t put Latics ahead on 17 minutes as he met a McLaughlin cross into the box but he skied over from six yards.
However, Latics did not dwell on that miss and took the lead midway through the half courtesy of an own goal.
It was great work from McLaughlin on the right, he put the ball into the danger zone and Pond struck the ball beyond his own goalkeeper to put Latics ahead.
And it was Athletic who looked the most likely to go on and get another with Erwin and Holloway linking well in attack.
More good work from McLaughlin followed on the hour half hour mark as he took the ball around two men and fell in the penalty area but the referee waved away the protests.
Banks came within a whisker of extending Athletic’s lead on 40 minutes.
The midfielder lined up a free kick from 25 yards, whipped it around the wall but Cairns managed to claw a hand to the ball and clear.
In the final minute of the half, Athletic almost doubled their lead through Erwin.
Holloway turned well in the penalty area before he laid it off to his strike partner but he curled over from 18 yards.
Fleetwood had a great chance after the break to equalise as Ball had space in the penalty area but volleyed wide of the goal.
Latics started to dominate possession in the second half and managed to get the second goal of the game on 55 minutes.
The ball was played into the chest of Erwin, he managed to turn inside the box and volleyed past Cairns to double Athletic’s lead.
Holloway picked up a knock on the hour mark and was replaced by Michael Ngoo and he was straight into the action.
He laid the ball into the path of Erwin whose curled effort was towards the far corner but Cairns managed to tip the ball behind for a corner.
Whilst the corner came to nothing, Athletic showed their dominance as they kept possession and took the sting out of the game.
Fleetwood went close with 20 minutes of the game remaining but Bobby Grant volleyed over from inside the box.
The visitors were forced to play the final 15 minutes of the game with 10 men after Bolger was forced off with an injury.
Latics almost made it three in the final five minutes of the game and it was excellent football which created the chance.
Green played it wide to Ngoo who drove at the defence, he crossed to Erwin in the centre but the striker stuck his brolly straight at Cairns.
However, that would not matter as Latics saw out the game comfortably and recorded a valuable win against promotion-chasing Fleetwood Town.
Oldham Athletic: Ripley, Wilson, Gerrard, Clarke, McLaughlin, Taylor, Green, Fane, Banks (O’Neill 87’), Erwin (Obadeyi 87’), Holloway (Ngoo 60’).
Subs not used: Law, Edmundson, Flynn, Croft.
Fleetwood Town: Cairns, McLaughlin, Pond, Ball, Grant, Bolger, Glendon (Dempsey 71’), Hunter, Woolford (Burns 62’), Davies, Schwabl (Maguire 46’).
Subs not used: Urwin, Brannigan, Eastham, Sowerby.
Goals: Oldham Athletic (Pond OG 25’, Erwin 55’) 2-0 Fleetwood Town
Attendance: 3,933 (425 visiting supporters)