The Jags won at a canter, leaving Queens facing a battle to avoid the drop.
Thistle showed the more fluidity throughout and took the lead in 17 minutes when Sean Welsh crossed for Kris Doolan, who controlled brilliantly and drilled the ball past goalkeeper Lee Robinson from 15 yards.
The Doonhamers, unbeaten in their previous four home league games, offered little in attack and Thistle doubled their lead three minutes before the interval after a defensive blunder allowed Stephen O’Donnell to tap in.
Thistle added a third in 64 minutes through Doolan and the fourth came in 70 minutes from Chris Erskine. Substitute Christie Elliot came off the bench to knock home a fifth from close range.