Heslop captained York to Buildbase FA Trophy victory against Macclesfield Town at Wembley Stadium in May this year.
The midfielder played against the Spitfires last season, scoring when the Minstermen visited The Silverlake in November.
Heslop spoke of his delight at joining up with the squad, telling the club`s official website: “I’m itching to get going – it’s only initially a one-month loan, but I’m excited to get started.
“This league is all about getting a consistent run going, and I’m sure with the squad assembled, we can give it a go”.
(Photo: Simon Heslop lifts the FA Trophy at Wembley in May)