Wolves scored the all-important goal in the eighth minute after Preston left-back Matt Hill had already been forced to twice clear the ball off the line.
The second rebound fell to George Olofinjana and he hit a 15-yard right-foot shot into the bottom right-hand corner of the net.
Preston's problems worsened in the 15th minute when striker Brett Ormerod fell awkwardly to the ground and was prostrate for a couple of minutes.
He had to be helped off the pitch with a suspected dislocated shoulder and Paul Simpson was forced to bring on substitute Simon Whaley to replace the former Blackpool star.
As North End hit back Michael Ricketts was fouled just outside the box before hitting a 20-yard right-footed free-kick that came back off the crossbar.
At the other end Michael McIndoe had a 30-yard left-foot shot saved by Preston keeper Andy Lonergan.
Kelvin Wilson was booked for a foul on Andy Keogh after 37 minutes and Olofinjana missed a chance to score his second goal of the afternoon just before half-time when he fired over the bar.
Early in the second half Stephen Ward had a ten-yard left-foot shot which went narrowly wide of the left-hand post.
Chris Sedgwick then hit over a right-foot, right-wing cross that David Nugent headed wide of the right-hand post.
The dangerous Keogh had a 15-yard right-foot shot from a right-wing cross brilliantly saved by the Preston keeper who tipped the ball around the post for a right-wing corner after 58 minutes.
Lonergan again made a great save to deny Darren Potter and Preston captain Graham Alexander had a 15-yard right-foot shot which rebounded off the left-hand post.
Preston brought on Neil Mellor for his Deepdale debut following the injury-prone striker's transfer from Liverpool to replace Danny Pugh and Mark Davies replaced McIndoe for the visitors.
With five minutes to go Wilson held back Keogh who was running down the right wing and the referee, Mr Laws, had no hesitation in showing a red card to the Preston player to end a dismal afternoon for Simpson's side.