David Nugent had a 12-yard shot after just nine minutes which deflected for corner off the Palace goalkeeper.
Brett Ormerod made a dream start on his debut for Preston following a free transfer from Southampton when he scored after 12 minutes.
Brian O'Neil managed to toe-poke the ball through to Ormerod after a mix-up by Mark Hudson and Mikele Leigertwood in the Palace defence and he hit 15-yard shot into the bottom corner of the net.
Ormerod had another shot saved by the Palace keeper after 20 minutes which was punched away from in front of the post.
Clinton Morrison should have done better when he volleyed over just four yards out and then he shot straight at Carlo Nash from eight yards after half an hour.
Claude Davis was booked for fouling Andy Johnson and Nugent was booked for fouling Hudson as the referee nearly lost control just before half-time.
Preston scored an important second goal after 49 minutes when a Graham Alexander corner was met by a bullet header from five yards out by O'Neil.
Johnson had a 20-yard shot well saved by Nash who dived to his left soon after.
Marco Reich was booked for dissent in the last minute as Palace ultimately ran out of steam.