Two second-half goals in quick succession from Ben Close and Kyle Hurst were enough to hand Doncaster a much-needed boost after Tranmere had earlier hit the woodwork through Ethan Bristow.
Visitors Tranmere created the best chances to score prior to the goal and also went close through captain Kane Hemmings, who was denied by Jonathan Mitchell from close range.
But a slice of luck saw Close break the deadlock when his deflected effort from outside the box flew over Mateusz Hewelt and into the back of the net on 62 minutes.
Three minutes later Kyle Hurst grabbed his seventh goal of the season with a well-taken finish after Charlie Lakin played him through one-on-one.
Brad Walker hit the bar in response for Tranmere but Doncaster held out comfortably to earn just their fifth clean sheet in League Two this term.
Scroll down for our ratings.
9. Charlie Lakin - 8
Probably Doncaster's best player. Looks neat and tidy on the ball and can get up and down the pitch. Assisted the second goal after stealing the ball back high up the pitch and quickly releasing Kyle Hurst. Photo: Howard Roe/AHPIX LTD
10. Kyle Hurst - 8
Doncaster's biggest threat in the first half and scored their second goal with a great finish after being played through one-on-one. Photo: Howard Roe/AHPIX LTD
11. Luke Molyneux - 6
A very quiet first half. Improved slightly after the break. Put a shift in but lacked quality going forward. Photo: Howard Roe/AHPIX LTD
12. George Miller - 7
Produced some good link-up play at times and, as always, couldn't be faulted for his work rate. Did look isolated at times, particularly in the first half. Photo: Howard Roe/AHPIX LTD