Penrith had a chance to level the Magic Round clash with a penalty which was pushed wide in the last minute by Dylan Edwards at Brisbane's Suncorp Stadium.
Brilliant rookie Warriors fullback Taine Tuaupiki nailed a late conversion from the sidelines to hand the the Warriors a narrow two-point advantage with the clock running down.
With 10 Warriors players missing from the clash due to injuries, the team had a makeshift look about it.
Captain Tohu Harris was missing from the side with a foot injury with Shaun Johnson also sidelined.
Te Maire Martin and Charnze Nicoll-Klokstad were inspirational leaders for the side, after the team was blown off the park by the Roosters 38-18 last weekend.
Martin told SkySport it was a significant performance for the club, which will give the side the belief they have been searching for.
"It means a lot, it really does," Te Maire Martin said after their fifth - and most unlikely - win of the season.
"We're stoked. We've been in a bit of a rut for the last couple of weeks and to come out with a win like that was huge.
"Having some of our big boys out, Tohu our captain and Shaun, and our real big dog Rocco Berry, it was a credit to the boys.
"Obviously Webby (coach Andrew Webster) coming from Penrith he had a few things up his sleeve."
Tuaupiki scored his maiden NRL try with Marcelo Montoya, Ali Leiataua and Adam Pompey also touching down.
Next round the Warriors will host the Dolphins at Mt Smart Stadium.
