The sides looked well matched in the opening exchanges of Tuesday's League Two clash at Highbury but it was Vale who made their pressure tell.
Just before the half hour, Jennison Myrie-Williams terrorised the home fence and slotted through for Tom Pope to shake off Dean Howells and power the ball past goalkeeper Scott Davies.
Six minutes later, Vale's Ashley Vincent found himself in acres of space and punished the Cod Army from the edge of the box.
Fleetwood stayed in the game thanks to a looping header from Junior Brown, but Vale finished them off ruthlessly.
Pope grabbed his second when he smashed John McCombe's parried shot beyond Davies and a brace from Louis Dodds in nine minutes finished off the home side. Dodds was gifted his first thanks to a disastrous Ashley Eastham back pass, allowing him to tap the ball home, and smashed a second home unmarked from inside the box after 68 minutes.
Dejected Fleetwood took solace in a penalty from substitute Steven Gillespie in the 83rd minute.