Paul Jewell's team have not lost at home since late August but they had to come from behind against a Preston team that stretched their unbeaten run to four matches.
All the goal action came in the first half with Derby opening the scoring against the run of play through Rob Hulse.
A Callum Davidson penalty and a Neil Mellor strike put Preston in control before Jordan Stewart levelled in the 32nd minute.
The second half produced plenty of chances but Preston keeper Andy Lonergan made three outstanding saves and a goal-line clearance denied Preston a winner.
The visitors began the match in confident fashion and it was a surprise when Hulse nipped in to slip the ball past Lonergan as the defence stood looking in vain for an offside flag.
But a rash challenge by striker Emanuel Villa gave Davidson the chance to equalise from the penalty spot in the 21st minute and then a defensive blunder gifted the visitors a second.
Davidson played a long ball from inside his own half and Stewart made a hash of his back-pass leaving Mellor to fire low past Roy Carroll from 16 yards.
There was an air of comedy about all the goals and Preston had two chances to clear a long throw before Stewart smashed a left-foot volley from the edge of the area into the bottom left corner.
The second half was dominated by Derby for the first half-an-hour with Lonergan touching Przemyslaw Kazmierczak's 25-yard free-kick on to the bar while Nathan Ellington had a low shot turned behind.
Billy Jones had a header cleared off the line in the 74th minute before Carroll tipped over a Chris Brown effort as Preston regained their authority of the first half.
But it was Derby that nearly won it nine minutes from the end when Hulse met a cross from the left but his header was saved at full stretch by Lonergan.