Kyle Bartley scored his first goal for Leeds to hand them their first home win since the middle of April.
The on-loan Swansea defender headed home a free-kick to deny bottom-placed Blackburn their second successive draw.
Substitute Chris Wood had put Leeds ahead when he tapped home Hadi Sacko’s right-wing cross from close range.
But Marvin Emnes equalised from the edge of the area with his first Rovers goal after good work by Ben Marshall and Craig Conway down the left.
There was little hint of the excitement to come during a first half which was only notable for a long injury stoppage after a clash between Leeds goalkeeper Rob Green and Blackburn’s Sam Gallagher.
Wood changed all that only five minutes after coming on when he gave Leeds the lead with his fourth goal of the season.
Blackburn, rooted to the bottom of the Championship table and without a win, equalised thanks to a spectacular finish from deadline-day signing Emnes.
But poor marking allowed Bartley to snatch the winner and earn Leeds their first home victory in five games.