First half goals from Marko Futacs and Martyn Waghorn were enough to earn the visitors all three points.
The best chance of the early stages fell to Leicester on ten minutes, when Jeff Schlupp ran clear of the Forest defence. Reds keeper Jordan Smith stood his ground and did well to block the winger's effort with his feet.
Four minutes later, Jak McCourt blazed over, before Forest responded through David Papworth, who saw his shot veer well wide.
And The Reds went even closer minutes later when Derrick Otim's low cross found Kieron Wallace, but the midfielder's shot was well blocked.
On 20 minutes, one-time Forest target Martyn Waghorn blazed a free-kick over Smith's crossbar.
A minute later, Peter Gregory's blocked clearance fell for Schlupp, whose square ball found Jacob Blyth. His shot trickled inches wide of the post.
The breakthrough did come for The Foxes on 30 minutes. Schlupp beat Gregory and crossed for Futacs, whose effort cannoned into the ground and beyond Smith.
On 35 minutes, England Under-19 international Ben Osborn nearly levelled for the hosts after a good spell of patient build-up, but his shot from range went just over.
The visitors had two chances in quick succession just before the break, with Smith called into action to deny both Futacs and Blyth.
And it was 2-0 shortly afterwards when Waghorn's 25-yard drive found the bottom corner.
Forest started the second half brightly and almost scored on 49 minutes. Otim got to the byline and did well to dig out a cross for Ferrier, but the striker couldn't control his header and it went over.
On 55 minutes, Schlupp his the post and George Taft couldn't convert the follow-up.
Three minutes later, Jack Blake's free-kick was tipped wide by a sprawling Conrad Logan. The experienced stopper did well to catch the resultant corner.
On the hour mark, Papworth was replaced by Michael Hollingsworth.
On 63 minutes, Ferrier chased down a long ball over the top. He got to it before Logan, but couldn't quite evade the attentions of the goalkeeper and it went out for a goal kick.
Seven minutes later, Futacs was back on the goal trail, but his shot from outside of the area went wide.
On 82 minutes, Osborn did brilliantly to trick his way to the byline but his progression was eventually halted by Logan.
Half chances fell to both sides in the dying moments, but the game ended 2-0.
Forest: Smith, Gregory, Fenton, Blake, Regan, Ackroyd, Papworth (Hollingsworth 60'), Wallace, Ferrier, Otim, Osborn.
Subs not used: Myles, Sebastiao, Thomas, Kamaneno.
Leicester: Logan, Pearson, Taft, McCourt, Sesay, Maduako, Panayiotou, Waghorn, Blyth (Paratore 73'), Futacs (Calum Brennan 90'), Schlupp.
Subs not used: Connor Brennan, Anton, Dodoo.
Scorers: Futacs 30', Waghorn 44'