The Canadian striker fired home with 15 minutes remaining after neat work from Jon Macken to seal the points in a game that seemed destined for a stalemate.
Up until Hume's third of the season the encounter hadacked any sort of quality, though Barnsley will feel they deserved the win after having the better of the game.
Blackpool, who are now winless on the road since Boxing Day, offered very little throughout the game and Luke Steele in the Barnsley goal was a virtual spectator without a save to make.
The defeat sees Ian Holloway's men miss the opportunity to climb back into the top six after Cardiff were beaten at Preston, while Barnsley's hopes of prolonging their season in May have been boosted and they now sit just four points adrift of the play-offs.
Barnsley came into the game on the back of an impressive win at Cardiff last week and boss Mark Robins made just one change to his side, with Ryan Shotton returning to defence after a suspension.
Blackpool, who won last week as well, also made one change as Gary Taylor-Fletcher was injured, so Ben Burgess came into partner DJ Campbell in attack.
Despite their positive results last week, both sides struggled to settle in a drab opening 45 minutes on a boggy Oakwell pitch.
Both defences were on top and neither Steele nor Blackpool's Matthew Gilks were tested in their respective goals.
It was the Tykes who controlled much of the possession, but they were unable to convert that into chances, with a blocked effort from Filipe Teixeira the best moment of an instantly forgettable first half.
The managers' half-time team talks did little to improve matters after the break as both sides were again void of attacking ideas.
Barnsley's Adam Hammill looked the most dangerous player on the pitch, showing plenty of endeavour down the left wing.
And it was Hammill who had the hosts' best chance early in the second half, but his low shot was well parried by Gilks.
Eventually the hosts were able to build up a head of steam and in the 75th minute
they took the lead that on balance they had just about deserved.
Bobby Hassell pumped a long ball forward for Macken, who expertly laid the ball into the path of Hume, and he fired the ball across Gilks and into the bottom corner.
Hume had only been on the pitch for a few minutes and notched his third of the season.
The goal gave the hosts extra confidence and they could have won by a bigger margin as Hume, Hammill, Macken and Colace all had decent chances.