George Lloyd’s opener for Shrewsbury was cancelled out by visiting striker Jonson Clarke-Harris’ penalty.
After a quiet opening 20 minutes, Shrewsbury broke the deadlock with Leo Castledine the architect, after he switched the play to Charles Sagoe Junior.
The forward found Mal Benning out wide, who delivered a cross to Lloyd to tuck away from close range.
The hosts went close to a second just before the half-hour mark when Castledine was played through on goal.
The creative midfielder let fly from the edge of the box, but his effort cannoned off the crossbar.
Rotherham came close to an equaliser just past the hour mark.
Cohen Bramall drove down the left flank before delivering a cross into the heart of the box, but Clarke-Harris headed wide.
The visitors won a penalty with just over 20 minutes remaining after a Benning high boot in the box.
Clarke-Harris took the spot-kick and converted it into the bottom right corner to earn the Millers a draw.