It was looking as though it would be a frustrating afternoon for the home team before Mike Williamson headed Stefan Oakes' free-kick back to McGleish who arrowed a right-footed shot into the bottom corner to notch his 26th league goal of a prolific season.
However, Chester will be looking over their shoulders at the relegation trapdoor as this result leaves them just two points clear of the drop-zone.
Russell Martin struck the bar for the home side on 18 minutes with the only clear-cut chance of a tight first half. Chester's opportunities were restricted to speculative long-range efforts, but they would have gone into the break pleased with their first-half effort.
Wycombe came out for the second period looking much more determined and Delroy Facey could have given them the lead almost immediately only to see his header tipped over by John Danby in the Chester goal.
Paul McManus wasted Chester's best chance on 50 minutes when he fired wastefully over from the centre of the box. But, after Facey had struck a post on the hour mark, it looked as though the visitors would escape with a vital point.
The lively Martin was increasingly influential in midfield for the home side who began to pile on the pressure and forced several corners, but Chester were also looking lively on the break as the game opened up.
But just as it looked as though Chester had weathered the storm, McGleish struck to set up a nervous couple of weeks for Simon Davies' side.