The Iron were in typically freescoring form, finding the net three times in the second half after a relatively even first 45 minutes.
Up to the break Chesterfield looked well capable of competing, but were unable to take any of their chances, before Graham Alexander’s side took over in the second half.
Top goalscorer Josh Morris got the party started for the 1,152 away fans with a free-kick, Kevin Van Veen and Sam Mantom adding emphatic finishes to simple, quick counter attacking moves.
The game started largely as expected, Scunthorpe pouring on the pressure from the very first minute, winning a free-kick in a good position and then a corner.
Chesterfield’s problem with set-pieces almost reared its ugly head again, Levi Sutton allowed to run onto the corner completely unmarked at the back post, his cross-cum-shot blocked and cleared.
Scunthorpe’s freescoring midfielde Josh Morris was handed an early opportunity when Sam Hird conceded a free-kick 30 yards out, keeper Ryan Fulton looked to have it covered as the ball curled over the bar however.
It wasn’t until the 18th minute that visiting keeper Luke Daniels had anything to do, taking a well hit Ched Evans shot relatively comfortably.
Chesterfield’s problem wasn’t so much breaking up attacks to win back the ball, it was keeping possession once they had it, Jay O’Shea and Gboly Ariyibi getting little joy on the flanks and unable to provide the necessary outlet.
Midway through the half Danny Wilson’s men did manage to fashion a very good chance and both O’Shea and Ariyibi were involved, the former finding the latter who crossed for Evans, the striker’s header flashing just wide.
Chesterfield were reminded of the potent attacking threat held by their visitors when, from their own attack, they very nearly conceded - a Dion Donohue error letting the Iron counter, Morris shooting just wide having had to avoid running into referee Oliver Langford.
In a see-saw period of play, back came Town, Ariyibi finding the feet of German just outside the box, the young striker taking it early and shooting the wrong side of the post on his full professional debut.
The hosts were well in the game in the half’s latter stages, Ariyibi dancing into the area and seeing a shot deflected wide, half the ground believing it had gone in.
An errant Donohue free-kick allowed Scunthorpe to break once more, Paddy Madden going clean through only to be denied by the legs of Fulton, the keeper sparing his left-back’s blushes.
And at the other end Liam O’Neil blasted a volley off target in the final action of the half.
Scunthorpe wasted no time after the break in taking the advantage, pressuring Chesterfield into errors and forcing Jon Nolan to concede a free-kick wide on the right, Morris’ subsequent effort going all the way through to the net without a touch. It was his 14th of the season and a disappointing one for the hosts to concede.
On the hour mark the Spireites had a mountain to climb, Duane Holmes showing his blistering pace, running right down the middle of the pitch and feeding Van Veen who took the ball into the box and shot home through Fulton’s legs.
Dan Gardner made an entrance in the aftermath of the goal, replacing German, and made an instant impact, crossing from the left and finding O’Shea who could only head straight up in the air.
Chesterfield’s frustration was evident in Tom Anderson’s reaction to giving away a free-kick in the opposition area, and their dismay increased when Van Veen played in substitute Sam Mantom who finished low and hard past Fulton.
The goal sparked a mass exodus at the Proact and resigned Town to an unenviable record of just one win in 11 league matches.
Chesterfield: Fulton, O’Neil (Simons 82), Donohue, Hird, Anderson, Liddle, Nolan, Ariyibi, O’Shea (Mitchell 70), Evans, German (Gardner 61). Subs: Allinson, Evatt, Dimaio, Graham.
Scunthorpe United: Daniels, Sutton, Townsend, Mirfin, Wallace, Holmes (Mantom 73), Morris (Goode 86), Dawson (Smallwood 79), Bishop, Madden, Van Veen. Subs: Anyon, Hopper, Margetts, Ness.
Referee: Mr Oliver Langford. Assistants: Mr Geoffrey Russell, Mr Adam Crysell.
Goalscorers: Morris 49, Van Veen 60, Mantom 85
Yellows: Anderson 83; Dawson 78
Attendance: 6,328 (1,152 away)