Blackpool looked set to claim the points but goals from Marc Richards and Brian Howard denied Blackpool the victory.
Simon Wiles and Tommy Wright grabbed the goals as Blackpool looked set to produce a welcome win.
The visitors went in front after 29 minutes when Wright crossed from the left and Wiles was left in space to rifle in a volley from eight yards.
Blackpool could have been further in front by half time but Nick Colgan had to save twice from Wright's stinging 30 yarder and a Jamie Burns shot on the run.
Barnsley's best early effort was a clever flick and drive from Daniel Nardiello and a deep cross from Martin Devaney that deceived Les Pogliacomi and was inches wide of the post.
But Wright added the second after 68 minutes when he volleyed in from six yards after Burns picked him out.
Blackpool - still smarting after last week's miserable defeat by Colchester - looked to be coasting to the win to ease the pressure on manager Colin Hendry.
But a bizarre goal pulled one back when Pogliacomi hit Richards with a clearance and it went into the net.
Immediately from the restart Barnsley won the ball and Devaney's cross was powered in by Howard.
Both sides had chances to snatch the victory with late efforts but blew the opportunities.
Blackpool striker Keigan Parker broke away as Paul Reid pulled up injured but scooped his shot over the top.
At the other end Nardiello carved out a chance but failed to cash in and let the visitors off the hook.