The Millers' third home defeat of the season came at the expense of the visitors back to back wins which sees them climb into the auto spots and Rotherham slip to ninth following Port Vale's win over Lincoln City.
Two goals from James Collins did the damage either side of half time, as Nicky Wroe added a penalty to the Shrews tally.
Collins tucked the ball home after turning Luke Ashworth in the area to give them the lead, but saw his pass moments later intercepted by Nicky Law as Mark Wright looked odds on to add a quickfire second.
Wroe then stroked home from the spot after Ashworth tripped Wright just inside the box after a blatent handball was missed by referee Phillips.
And they made the game safe just after the break with a freak goal as Andy Warrington smashed the ball straight into Jon Taylor, giving Colllins a simple tap in.
Substitute Adam Le Fondre finished off fellow sub Omar Daley's tidy pass with 18 minutes remaining with a crisp effort but after a touch of late pressure the Millers slumped to a dissappointing defeat.
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