A brace by Chris Iwelumo and a 63rd minute Sylvan Ebanks- Blake strike sealed a comfortable victory for the side then managed by Mick McCarthy in this Championship encounter.
The win for the visitors was Wolves seventh in a row and it left them six points clear at the top of the table.
Strong start for the Wanderers
Wolves got off to the perfect start when Michael Kightly slipped in Iwelumo, who after rounding Paddy Kenny, slotted home.
The Blades had two chances to level shortly, first through Billy Sharp but his effort was close down by the onrushing Carl Ikeme.
Then Greg Halford somehow failed to find the target with his header from three yards out.
For Wolves, Neil Collins headed off target and Kightly fired just wide from outside of the area.
Ten minutes before the break Ikeme pulled out a fantastic one handed stop to keep out Matt Kilgallon's sweetly hit volley.
No goal given decision costs United
Almost immediately after the restart United felt they should have been level when a Brian Howard corner looked to directly cross the line, but no flag was raised by the linesman indicating that this had been the case.
Not long later, Hennessy produced two fine saves to keep out efforts by James Beattie.
The Blades would soon to live to regret these opportunities just before the hour mark when Iwelumo double his own and the Wanderers tally, when he smashed home from 10 yards after latching on to a Karl Henry cross.
Ebanks- Blake seals win
Four minutes later, the three points were secured when Kightly fed Ebanks- Blake who fired the ball into the top corner.
Matthew Spring grabbed a consolation goal with 15 minutes remaining from inside of the penalty area, but ultimately it was too little too late for the hosts.
This impressive victory for Wolves at a place which is never easy to go and pick up three points at, contributed to them winning the title that season, and consequently meaning that they earned promotion back to the Premier League after their five year absence from the top flight.