Barnsley went ahead after nine minutes but could have put the result beyond the visitors by half-time but for the heroics of Wolves keeper Matt Murray.
But then they had to survive a second-half battering before chalking up their first home win since February and their first clean sheet in 13 matches.
The crucial goal came when Michael McIndoe flighted in a perfect corner for Paul Heckingbottom whose downward header had Wolves in a panic as they tried to scramble it clear. But it broke to Marc Richards who stabbed in a close-range shot.
Wolves, third in the table, struggled to create early chances against the Oakwell-based side that have the worst defensive record in all four leagues this season having shipped a staggering 18 goals in their seven outings before this game.
But when Lewis Gobern sent a free-kick into the Tykes area, Jay Bothroyd's header sailed over the top and a Rohan Ricketts shot from the edge of the area was straight at the keeper.
Barnsley might have stretched their lead after 20 minutes when Martin Devaney tore down the right and his near-post cross was met by Paul Hayes whose glancing header was superbly turned away with a finger-tip save from Murray.
At the other end, when Barnsley let in Ricketts, his cross from the left found Bothroyd who had a free header but glanced it wide.
But Barnsley could have been out of sight by half-time as they ran Wolves ragged and in a frantic end to the hal, Sam Togwell drilled a 20-yard effort wide.
Murray produced a brilliant save to tip over a glancing header from Richards and then Antony Kay was just off target with a header from McIndoe's corner.
Howard, Richards and Hayes linked smartly before Hayes slipped past Mark Little and got in a shot that beat the keeper only for Rob Edwards to clear off the line. And Murray produced another stunning stop to deny a Kay effort.
After the break Wolves brought on substitute Leon Clarke for Bothroyd and he was involved in an early chance, setting up Ricketts who fired straight at the keeper from 12 yards.
But after a half-time rocket from Mick McCarthy, Wolves charged head-long looking for a leveller and giant strikers Clarke and Carl Cort were brought of the bench to help out. However, it was all in vain as the Tykes held on to secure three vital points.