George Elokobi gave Latics the lead on the half hour mark and two minutes later, Amari Morgan-Smith doubled the lead with a neat finish past the goalkeeper.
First half substitute Jonathan Forte wrapped up the game in the second half as he headed home his 14th goal of the season to seal a superb victory.
Latics started the game brightly, dominated possession and maybe should have been ahead on five minutes.
Dominic Poleon, who was starting his third game in succession, smashed over the bar after being presented with a chance from eight yards.
Liam Kelly and Mike Jones received a lot of the ball early on and looked to split open the Notts County defence.
The game started to get scrappy and Notts took a foothold on the game on 20 minutes.
Debutant Jake Kean was forced to tip over a Will Hayhurst free kick mid way through the half as County knocked on the door of the opening goal.
The visitors almost profited just before the half hour mark as Brian Wilson misread a pass back to him but the defence managed to recover and clear the danger.
Minutes later, Latics took the lead through the head of birthday boy, George Elokobi.
Morgan-Smith's shot was blocked as far Kelly who crossed perfectly onto the head of Elokobi and he wrong-footed the goalkeeper to give Latics a one goal advantage.
The Magpies goalkeeper made himself unpopular with the home supporters and was booked by the referee for dissent after the first goal.
The home side were rocking and two minutes later, they extended their lead courtesy of Morgan Smith.
The striker latched onto a perfectly weighted through ball over the top by Carl Winchester and finished confidently past Carroll to extend the home side's lead.
Athletic were in the ascendancy and Jones almost released Poleon through on goal five minutes before the break but the striker could not latch on to it.
Morgan-Smith was forced off with injury on 42 minutes and received a standing ovation for his efforts.
Latics had to be aware just before the break as County led siege on the home side's goal. An inswinging corner was almost put away at the back post but between Connor Brown and Kean, Latics managed to clear.
County started the second half strongly and could have pulled back on 50 minutes. Haydn Hollis rose highest from a corner but could not direct his header on target.
Latics did have the chance five minutes later to extend their lead. Winchester won the ball on the edge of the Magpies box and the ball ricocheted into the path of Forte.
The forward fed Poleon who was in acres of space in the box but shot straight at Carroll and the chance went begging.
Five minutes later, Poleon was presented with an even better chance to open his account for the afternoon but again he was denied by Carroll.
From that resulting shot, the ball was cleared into the path of Winchester who shot from the edge of the box but Carroll pulled off a wonderful save to deny his Northern-Ireland teammate.
Jonathan Forte, who was brought on to replace Morgan-Smith, almost scored an acrobatic effort from the resulting corner but the crossbar denied the forward of his 14th goal of the season.
Latics started to dominate proceedings and looked the most likely to extend their lead.
Danny Philliskirk forced a smart save from Carroll on 67 minutes and Forte volleyed wide on 70 as the home side were threatening.
On 73 minutes, they did make that pressure count as they went three goals ahead.
Winchester dummied the ball into the path of Brown; he crossed perfectly on to the head of Forte who powered his 14th of the season past Carroll.
Latics were not settling for three and went in search of the fourth goal but had to be aware as County looked to threaten on the break.
Crosses and corners were coming into the Athletic box but Kean demanded his area and thwarted the danger.
Latics kept possession well and saw out the game professionally and the result puts Latics up to 10th position, two points outside the Sky Bet League One play off places.
Oldham Athletic: Kean, B.Wilson, J.Wilson, Elokobi, Brown, Kelly, Jones, Winchester (Dieng 79'), Philliskirk, Morgan-Smith (Forte 42'), Poleon (Mellis 63').
Subs not used: Rachubka, Lockwood, Kusunga, Turner.
Notts County: Carroll, Dumbuya, Mullins, Hollis, Hayhurst, G.Thompson (Thomas 46'), C.Thompson, Noble, Woolery, Bajner (Daniels 67), Cranston.
Subs not used: Adams, Smith, Jones, Edwards, Pilkington.
Goals: Oldham Athletic (Elokobi 30', Morgan-Smith 32', Forte 73') 3-0 Notts County
Attendance: 3,494 (261 visiting supporters)