An early goal from Callum Camps, followed by a second-half Ian Henderson header, ensured Dale picked up their third win in as many games at the Crown Oil Arena on Tuesday night.
Brian Barry-Murphy named an unchanged side to the one which beat Bolton 3-1 at the weekend.
The deadlock was broken with just three minutes on the clock after a well worked set-piece found its way to Camps, who’s fierce strike nestled in the back of the net. There was confusion as to whether Matty Done got a slight touch before it crossed the line, but the goal was awarded to Camps.
MK Dons went in search of an equaliser with their first chance falling to Jordan Bowery, who headed over the bar.
Done then found himself with the chance to double Dale's lead, after he got on the end of an Eoghan O’Connell pass, but his curled effort went over.
Some good play from Rhys Norrington-Davies resulted in another Dale corner, from which the ball came out to Norrington-Davies, whose shot whistled just past the post.
Dale’s left back went close once more in the 19th minute, with another well struck shot going just wide.
Some superb defending by Eoghan O’Connell prevented Dons midfielder Callum Brittain equalising for the visitors.
MJ Williams was the next to go close for Dale, his shot cannoning back out off the post, with Callum Camps unable to convert the follow up.
The second-half followed with a similar pattern to the first, Dale searching for a second goal, and they nearly got it when Ollie Rathbone floated a cross into the box, which was just too high for Ian Henderson.
MK Dons then went close through Callum Brittain once more, who’s cushioned shot found only the side netting.
However, it was Dale who would go on to grab the all-important second goal, with Ian Henderson rising highest from an Aaron Morley corner to score his eighth goal of the campaign.
That goal gave Dale some breathing space and allowed for the introduction of Fabio Tavares, who was fresh from scoring his first goal for the Club on Saturday.
Tavares found himself with a great chance to grab his second in four days, getting in behind the MK Dons defence, but he couldn’t hit the target.
Second half substitute Kieran Agard went close for the visitors, but his header went wide.
Dale defended resolutely and held out for all three points comfortably, recording their fourth clean sheet of the season.
The win sees Dale move up to 11th place in Sky Bet League One.
Next up is Oxford United at the Kassam Stadium on Saturday, with ticket details HERE.