Barnsley finally won a home game for the first time since the 4th November, ending a club record 12 Oakwell outings without a victory.
The Reds won a league game after falling behind for the first time since the 21st January 2017 when they also won 3-2 against a Yorkshire rival, Leeds United.
It is however the second time this season that Barnsley have won after being 2-1 down as this also occurred in the 3-2 EFL Cup triumph over Derby in September.
This was Barnsley's first Yorkshire derby victory in eight, since a 1-0 victory at Rotherham in January 2017.
Barnsley went 1-0 up, 2-1 down and then won 3-2 for the first time since August 2016 against QPR. In that match The Reds reversed the deficit in the 77th and 89th minute whereas yesterday they did it in the 74th and 88th.
Tom Bradshaw's 88th minute winner was the latest Barnsley have scored a goal since Ethan Pinnock rescued a 1-1 draw against Reading in the 91st minute back in December.
It was the striker's first goal of 2018 and his 11th of the season and he is the first Barnsley substitute to score in eight matches.
Oli McBurnie grabbed his seventh goal for the Reds, all coming in 10 appearances.
Seven of Barnsley's last 13 goals have been scored by McBurnie, 10 of the last 15 have been scored by either McBurnie or Kieffer Moore, the only other players to score during this time are Brad Potts, Gary Gardner and Bradshaw.
Barnsley scored more than twice in a Championship game for only the fourth time this season, it is only the second time they have scored more than twice at Oakwell, the 3-0 August win over Sunderland being the other.
Barnsley led at half time for the 10th time in the Championship this season but then went onto win for only the fourth time.
This was only Barnsley's second win in nine Oakwell meetings with Sheffield United (D4 L3)
Barnsley have though won each of the last two Oakwell Championship meetings.
It is only their third win in 16 meetings home or away.
This result also ended Sheffield United's 10 match unbeaten league run against fellow South Yorkshire sides, of which they had won seven including victory over The Reds at Bramall Lane in August.
Leon Clarke scored United's second goal, meaning he has now scored 17 league goals in 2017-2018, only in 2012-13 (19) has he registered more in a single campaign.
This was the third time Clarke has scored against Barnsley, all three have come at Oakwell for three different clubs, Sheffield Wednesday in 2008, Coventry in 2014 and Sheffield United 2018.
Sheffield United had 63% possession in the game, the most an opponent has enjoyed at Oakwell since Fulham (64%) in January.
Sheffield United won 11 corners, the second most from an opponent at Oakwell this season after Leeds (12)
Adam Hammill (for Isgrove 59)
Tom Bradshaw (for Moncur 69)
Dimitri Cavare (for McBurnie 90+3)
Jack Walton, Ethan Pinnock, Stevie Mallan, Connor Mahoney.
Sheffield United Team:
Simon Moore, Chris Basham, Jake Wright, Jack O'Connell, George Baldock, John Lundstram, Lee Evans, John Fleck, Enda Stevens, David Brooks , Leon Clarke.
Billy Sharp (for Evans 39)
Mark Duffy (for Brooks 49)
James Wilson (for Wright 90+1)
Jake Eastwood, Ryan Leonard, Daniel Lafferty, Ricky Holmes.
Sheffield United manager Chris Wilder said:
"They were the better team in the first half so we changed a couple of things and for 20-25 minutes we absolutely dominated the game.
"We got ourselves back into it, went in front, and from then on there should have only been one winner.
"It's a very valuable three points for them and a damaging result for us.
"I think we're a really good side, but we're just missing something that wraps up games and the damage today is difficult to take."
Sky Bet Championship results:
Friday 6th April 2018:
Cardiff City 0-1 Wolverhampton Wanderers
Saturday 7th April 2018:
BARNSLEY 3-2 Sheffield United
Gardner 25 Fleck 57, Clarke 65
Norwich City 3-1 Aston Villa
Murphy 45+2 Grealish 67
Birmingham City 1-1 Burton Albion
Jutkiewicz 87 Dyer 48
Brentford 1-0 Ipswich Town
Maupay pen 72
Derby County 3-0 Bolton Wanderers
Hull City 4-0 Queens Park Rangers
Smithies og 45+4
Leeds United 1-1 Sunderland
Hernandez 72 McNair 48
Middlesbrough 2-0 Nottingham Forest
Millwall 2-0 Bristol City
Reading 1-0 Preston North End
Sheffield Wednesday 0-1 Fulham
Barnsley lie in 22nd place in the Sky Bet Championship with 37 points from 40 games.
We are 29 points outside the Play-Offs, 43 points off the Automatic Promotion Places, 52 points off First place and 2 points inside the Relegation Zone.
Up to 07/04/18
On The Road:
Sky Bet Championship Matchday Thirty Forty One: Ipswich Town v Barnsley: Tuesday 10th April 2018. Kick-Off: 7:45pm
Sky Bet Championship Matchday Thirty Forty Two: Barnsley v Bolton Wanderers, Saturday 14th April 2018. Kick-Off: 3pm