Recalled midfielder Lewis McGugan's second-half brace earned Forest a deserved first victory of the season - and their first away win since January.
The Reds dominated the game, but fell behind right on half-time to Jon Parkin's strike. But McGugan struck twice in the second-half as Forest earned three points.
Preston had the first chance of the game inside two minutes, but Parkin pulled his shot well wide of Lee Camp's left-hand post when well placed.
McGugan then forced Andy Lonergan into a sharp save after 10 minutes. McGugan played a neat one-two with Paul McKenna but, after cutting inside the defender, saw his shot well saved.
Nathan Tyson then missed a glorious chance to put Forest ahead as the Reds stepped up their game.
After playing in Dexter Blackstock on the right wing, Tyson made good ground to get on the end of Blackstock's cross, but, unmarked four yards out, he failed to get decent contact and could only watch as the ball bounced down and wide.
Another good move between Guy Moussi and Tyson found McGugan on the edge of the box, but, after turning away from his defender, he shot over under pressure.
With Forest dominating play, Gunter was next to miss a chance. The Welsh international fired straight at Lonergan after seizing on a wayward Preston pass on the halfway line and charging goalwards.
McGugan then flashed a shot across Lonergan and wide of his right-hand post from the edge of the area after a clever short corner involving Chris Cohen and Tyson.
However, as half-time neared, Preston began to enjoy some possession - and the home side made it count three minutes before the break.
Blackstock gave the ball away cheaply in midfield and Paul Coutts ran forward, before playing in Parkin. Parkin evaded Morgan's diving challenge and kept his composure to fire past Camp's right hand and into the net.
Camp was the first keeper in action in the second half, pouncing on Keith Treacy's low free kick after Tyson had harshly been adjudged to have fouled Sean St Ledger.
With Forest pressing for an equaliser, the game became more open and Lonergan was grateful to gather Paul Anderson's cross with Blackstock inches away.
Preston's fans were screaming for penalty minutes later, when the ball appeared to hit Morgan's arm, but the ref blew for a foul on Morgan by Parkin.
And from the free kick, Forest went straight up the other end and equalised. Tyson played the ball to McGugan who ran 10 yards before letting fly with a low shot from 25 yards which Lonergan got a hand to, but could not keep out.
Camp was then called into action, sticking up an arm to parry away Paul Parry's vicious free kick.
From the corner, Camp was grateful to see St Ledger's header pass inches wide of the post.
Another Forest break ended with Blackstock heading Tyson's excellent left-wing cross over the bar.
McGugan then wasted a great chance to score, seeing his shot saved by Lonergan after being put clean through by Anderson.
But Forest got their deserved second after 80 minutes.
After good work by Cohen on the left wing, his cross was touched by Blackstock to McGugan who smashed the ball into the roof of the net from eight yards.
Anderson then missed a glorious chance to seal the game with a minute to play. After excellent work by Dele Adebola in the middle, he played in Anderson, who smashed his shot well wide with just Lonergan to beat.
And Forest were nearly punished when Camp had to dive full stretch to his left to tip away Darel Russell's shot in added time, but the Reds held on for the win.
Forest: Camp, Gunter, Morgan, Wilson, Bertrand, Tyson(McCleary 73min), McKenna, Moussi(Anderson 64min), Cohen, McGugan(Adebola 86min), Blackstock
Subs not used:Darlow(GK), Chambers, Majewski, Thornhill
Scorer: McGugan 69min, 81min
PNE: Lonergan, Gray, Morgan, Davidson(C), St Ledger, Coutts(C Brown 82min), Treacy(Mayor 60min), Barton, Russell, Parry, Parkin.
Subs not used: W Brown, Hayes, Arestidou, McLaughlin, Wright.
Bookings: Parkin 88min
Scorer: Parkin 42min