They maintained their 100 per cent record for the season, a great start for Lilywhite manager Alan Irvine.
A crowd of 14,225 saw Barry Nicholson score on his home league debut and Richard Chaplow score in the last minute to give Preston all three points.
Palace had an early chance after ten minutes when James Scowcroft hit an 18-yard right-foot shot which went wide of the keeper's left-hand post.
Sean St. Ledger had a 12-yard header a minute later pushed away by Palace keeper Julian Speroni, who was replacing Darryl Flahavan in goal.
Preston right-winger Chris Sedgwick had a six-yard right-foot volley which went wide of the keeper's right-hand post after half an hour and Simon Whaley hit a 25-yard right-foot shot over the bar.
Andy Lonergan made another save from Lee Hills and then Nick Carle fired over the bar from 20 yards.
Right on half-time Lonergan saved from John Oster and then he tipped a Hills shot around the post.
Early in the second half Carle shot wide. Preston's opening goal came in the 58th minute when Calum Davidson crossed to Neil Mellor and he had a right-foot shot from six yards which the keeper could not hold and Nicholson hit a six-yard right-foot volley low into the centre of the net.
Hills had a six-yard right-foot shot tipped round the right-hand post by the Preston keeper and Mellor shot narrowly wide.
Scowcroft had a header which went over the bar and then Lonergan tipped over Scowcroft's right-foot shot from 25 yards.
Tom Soares hit a shot over the bar and Whaley put one wide.
Scowcroft had another header saved before Mellor hit a 12-yard right-foot shot wide of the Palace left-hand post.
Chaplow scored the clincher in the last minute when Billy Jones played a right-wing assist and Chaplow found the bottom left corner from six yards right-footed.