Huddersfield: (18) 41
Tries: Drew, Crabtree, Wild, Reilly, Hudson, Snitch
Goals: Thorman 8
Drop-goal: Thorman
Hull KR: (10) 22
Tries: Leuluai, Vaealiki 2
Goals: Richards 2
Huddersfield climbed off the bottom of the Super League table with their third consecutive win. The game was poised at 18-10 to the Giants until Wigan's Mark Calderwood was sin-binned after 47 minutes for a cynical foul on Stephen Wild.
With a man over, the home side raced into a 34-10 lead with tries from Paul Reilly and Ryan Hudson and a penalty from Chris Thorman.
There was no way back for Wigan, who slipped to sixth in the table.
Huddersfield coach John Sharp:
"We followed our game plan to perfection and I am really pleased with all the players. "The work we have done earlier in the campaign is now starting to pay off.
"We have gone from adversity to a position from where we can now go forward. I hope we can keep the momentum going."
Wigan coach Brian Noble:
"We looked very poor while Huddersfield played really well and had the right tactics for the conditions. "We have learned a big lesson. Players cannot just turn up and hope that their heads are in the right place.
"They have got to be better prepared than that and it is a lesson we will have to carry through for the rest of the season."
Huddersfield: Reilly, Aspinwall, Nero, Brown, Lolesi, Thorman, Drew, Mason, Hudson, Skandalis, Wild, Raleigh, Snitch
Replacements: Crabtree, Jones, Jackson, Griffin
Wigan: Ashton, Calderwood, Bailey, Vaealiki, Richards, Barrett, Leuluai, Fielden, Millard, Paleaaesina, Hock, Hansen, O'Loughlin
Replacements: Higham, Prescott, Goulding, O'Carroll
Referee: S Ganson (St Helens)