Ade Akinbiyi struck with a late equaliser to continue Stoke's unbeaten start to the season and rob Rotherham of their first win.
Ronnie Moore's side were on course for victory after loan hero Paul Shaw struck his second goal for the club 11 minutes after the break.
But Akinbiyi slid in a close-range shot five minutes from the end after keeper Mike Pollitt had parried Lewis Neal's header.
Shaw, who is on a three-month loan at Millmoor from Sheffield United with a view to a permanent deal, gave Rotherham a 56th minute lead with a cool finish from 20 yards after Chris Sedgwick's shot hit a defender.
The loanee has scored both Rotherham's goals in their first three games as the relegation favourites have made an unbeaten start to the season.
Stoke striker Gifton Noel-Williams played after the FA overturned his three-match ban following Tuesday's controversial red card at Sheffield United and the big frontman was the first to test Mike Pollitt with an early header.
The Millers had a strong appeal for a penalty dismissed by referee Keith Hill after 20 minutes as they looked to break the deadlock.
Chris Swailes went down in the area under pressure from former Northern Ireland international Gerry Taggart but failed to persuade the official it was unfair.
Noel-Williams spun in the area and hit a dangerous ball across the Rotherham area and then hoisted a close-range effort over.
Clive Clarke should have done better when the referee played on after Akinbiyi was downed, but Clarke lifted a shot over after cutting inside.
It was Akinbiyi who created another opening two minutes before half-time using his strength to hold up the ball. Marcus Hall slammed a 25 yarder. but Pollitt saved well.
It was Rotherham who broke the deadlock after 56 minutes before Akinbiyi sparked celebrations from the visiting fans with his equaliser.