Scott McDonald scored only 15 minutes into his Thistle debut to help move his new side out of the relegation zone and send Alloa to the foot of the table.
The former Australia internationalist spurned a glorious chance minutes after his introduction when he skewed over the bar but he made amends soon after.
Fellow substitute Lewis Mansell grabbed an assist with his first touch, nodding the ball down for McDonald to stab home.
Thistle had allowed Alloa to grab a foothold in the game despite taking an early lead when Kris Doolan collected the ball in the box with his back to goal and cushioned it back to Blair Spittal who rifled a left-footed shot past Neil Parry. Spittal almost grabbed his second on 11 minutes when he collected Jack McMillan’s long ball but Parry made a smart save at his near post.
Thistle spurned two opportunities to double their advantage. First Gary Harkins had a goalbound effort cleared off the line by Kevin Cawley before McMillan’s effort hit the bar.
Alloa battled valiantly throughout, with Steven Anderson and McMillan producing great defensive clearances to deny them, but the Wasps face an uphill battle to avoid the drop.