Goals from Rob Hulse and an own goal by Karl Duguid cancelled out a stunning opener from Paul Gallagher which had given the visitors the early control.
Derby would have almost certainly have lost earlier in the season but there is a growing belief and confidence in the team and, despite losing Steven Davies with a facial injury, they regrouped to draw level before half-time.
There had been little in the way of quality apart from Gallagher's dipping volley from 22 yards from the right-hand edge of the penalty area until Kris Commons' streak down the left in first-half stoppage time.
He outpaced Chris Clark before slipping inside Chris Barker and his low cross was cleverly controlled by Hulse, before he slid a low shot from eight yards inside the right-hand post.
The goal lifted Derby and Plymouth were trailing seven minutes after the break.
Commons forced a corner and when the ball was only half-cleared, Paul Green lashed in a shot from the edge of the box which was pushed on to a post by Romain Larrieu before Duguid put the ball into his own net as he desperately tried to clear.
Plymouth showed their spirit by forcing Derby back and created the chances that should have earned them a point in the last ten minutes.
Duguid had a low shot saved by Stephen Bywater, who then dropped a cross only for substitute Nicolas Marin to head wide.
Marin had another chance in the 89th minute when Luke Summerfield lifted the ball over the defence but he put his shot into the Plymouth supporters behind the Derby goal.