Paul Wotton's eighth goal of the season proved enough to secure the points for Plymouth and piled more misery on relegation-threatened Leicester.
Wotton fired home a free-kick early in the second half but, despite a valiant fightback, the Foxes were unable to find a goal to leave them still searching for a first win of 2006 in the Coca-Cola Championship.
The visitors were hoping to bring an end to a run of five successive league defeats against Tony Pulis' side, who were out to build on a morale-boosting 2-1 success at Crewe at the weekend.
The home side dominated from the start, David Norris the first to test Leicester goalkeeper Rab Douglas in the 10th minute when his volley from the middle of the box was caught by the Scotland international.
Patrick McCarthy then headed wide for Leicester. But the Pilgrims again came forward as Nick Chadwick drilled his effort over the bar from 18 yards and then Tony Capaldi sent his free-kick just over.
After that, chances for either side petered out until seven minutes before half-time - and it was again Plymouth who were close to breaking the deadlock.
Wotton's header was tipped over by Douglas, before Capaldi's corner was cleared to safety by Nils-Eric Johansson.
The Foxes were struggling to find a way through, and the best chance they had before the break came from Joey Gudjonsson whose low shot from distance was blocked by Norris.
Micky Evans was next to test Douglas, but his header was caught by the 'keeper just before the interval.
However, Plymouth were ahead just two minutes into the second half when a foul by Patrick Kisnorbo on Evans presented the Pilgrims with a free-kick in a promising position.
Wotton, who had been one of the main factors for Plymouth's dominance in the first half, stepped up to fire an unstoppable shot beyond Douglas and into the back of the net.
The goal seemed to have a positive effect on the visitors and they started to pour forward.
Recent signing Matty Fryatt saw his shot blocked before Alan Maybury's decent effort was parried to safety by Romain Larrieu soon after.
Gudjonsson fired wide when he drilled a shot from distance and it looked like an equaliser could soon be on the cards.
But, for all their dominance Leicester were still failing to produce the necessary spark in front of goal.
Mathias Doumbe should have put the game beyond Leicester in the 78th minute but his header from six yards after a Capaldi corner fell wide of the goal.
Richard Stearman's overhead overhead kick deep into injury time was blocked by Doumbe leaving the Foxes precariously placed in the Championship relegation zone.
Teams
Plymouth (0) 1 Leicester (0) 0
Plymouth Larrieu, Barness, Doumbe, Ward, Aljofree, Norris, Wotton, Nalis, Capaldi, Evans, Chadwick.
Subs Not Used: Buzsaky, Hodges, McCormick, Zebroski, Djordjic.
Booked: Capaldi.
Goals: Wotton 47.
Leicester Douglas, Stearman, McCarthy, Johansson, Maybury (Smith 57), Hughes, Gudjonsson, Wesolowski, Kisnorbo, de Vries (Hume 70), Fryatt (Hammond 70).
Subs Not Used: Hamill, O'Grady.
Booked: Gudjonsson.
Att: 12,591
Ref: A Woolmer (Northamptonshire).