Rovers were superbly led by stand-in skipper Leo Fortune-West and hustled the visitors out of their stride from the start.
On-loan striker Johnathan Forte had a shot deflected for a corner in the 14th minute after bursting clean through.
And the home side took the lead when the resulting corner was only partially cleared a minute later.
James Coppinger latched on to the ball and passed to the far post where Paul Green knocked it back for Fortune-West to head home in powerful style.
Scunthorpe were always second to the ball as Rovers won the vital tackles and they made in 2-0 in the 25th minute.
A deep cross from Coppinger on the right found Michael McIndoe unmarked at the far post and he drove home a low shot.
Coppinger went close to adding a third when he dribbled past three defenders in the 31st minute, but it needed a last-ditch tackle from Mark Albrighton to prevent Andy Keogh pulling one back on the stroke of half time.
Scunthorpe were back in the game in the 51st minute when Billy Sharp hammered the ball home following a goalmouth scramble and a rare mix-up in the home defence caused by some neat play from Cleveland Taylor on the right.
But the revival only lasted nine minutes when Doncaster reasserted themselves to add a third goal.
Forte scored in splendid style with a curling shot from a difficult angle after latching on to a superb pass from Uros Predic.
Doncaster were good value for the win and went close to snatching a fourth goal when substitute Ricky Ravenhill hit a scorching 20 yarder inches wide in injury time.