Preston players celebrate Lewis Moult's goal
Lewis Moult scored the only goal of the game as Preston ended Nottingham Forest's five-game unbeaten run.
Forest had scored nine goals in their previous three games, including five in their 5-5 draw with Aston Villa.
But they were kept at bay by Preston keeper Declan Rudd, whose fingertip save denied Daryl Murphy with the visitors in front.
Moult had found the net from close range in the 56th minute following a goalmouth scramble.
Aitor Karanka's side missed several chances to score and the opportunity to leapfrog West Brom and Middlesbrough into fourth place had they won at the City Ground.
Tendayi Darikwa and Joe Lolley were both denied by Rudd before the visitors almost undid the hosts' bright start when Tom Barkhuizen's was saved by Costel Pantilimon.
Preston sub Lukas Nmecha almost scored an own goal when his looping clearance landed on the roof of his own net.
Matty Cash then fired wide for Forest before seeing Rudd turn away another effort after the break.
The visitors took the lead as the Forest defence failed to deal with an Nmecha cross that was turned in by Moult.
And Ryan Ledson's low shot almost made it 2-0 before substitute Daryl Murphy's header was turned away by Rudd at the other end as Alex Neil's claimed their third win in five games.
Nottingham Forest manager Aitor Karanka said:
"I think the only thing we missed was scoring goals. In the first half in particular, we played really well and we should have been winning 2-0 or 3-0 by half time, if not by more.
"But we did not play the same in the second half. We finished the game with Lewis Grabban and Daryl Murphy up front and we started to play in the wrong way; we started to play long balls and we do not know how to play in that way.
"I do not know if it is difficult to retain the dominance we had in the first half for 90 minutes - but that is what we have to do. In the Championship, every single mistake you make is punished.
Preston North End manager Alex Neil said:
"We have now lost one game in 11 which is some going at this level. And we have still got four or five players out, players who are key figures. Ben Pearson is a talisman for us and Callum Robinson is our top scorer.
"We knew that if we went toe-to-toe with them, it would be a tough game. We had a plan in place, we wanted to be narrow and stop them playing in the pockets they like to occupy.
"I thought our gameplan worked very well. But it is one thing having a plan and it is another carrying it out. I thought the players carried it out to a tee."
