Petrov, 36, has been recovering from an acute form of leukaemia, which was first diagnosed in 2012.
But he has now been invited to join up with Villa for their pre-season training camp in Austria on 7 July.
The 105-times capped Bulgaria international is still hopeful of making a return to football.
And, although it is now three years since he officially retired from professional football, Villa have always kept the door open for him.
He is now looking to improve his fitness ahead of the new season, as he needs group training at a level higher than that at which he has been playing.
He has initially been invited to train for a month on a non-contract basis with Villa, who start life in the Championship with a trip to face Sheffield Wednesday at Hillsborough on 7 August, having been relegated to the second tier for the first time since 1987.
Petrov was then Villa boss Martin O'Neill's first signing when he arrived from Celtic for £6.5m in August 2006.
He first showed symptoms of leukaemia after developing a fever following a 3-0 defeat at Arsenal in March 2012 and was diagnosed with the disease a few days later after making 218 appearances for Villa and more than 500 in British football.
He had four months of chemotherapy before it was announced in August of the same year that the disease was in remission.
Fuelled by the love and support of the Villa fans, he has since set up a foundation to help leukaemia sufferers.
"For both sides this makes a lot of sense.
"Petrov can continue to get fitter and fitter in an environment he's familiar with around people that respect him.
"For Villa, if he proves to be fit enough to make a return to the game then they'll surely have first refusal on his services.
"He'll learn a lot about how his body is when he joins up with Villa in Austria and flies into his first 50-50 challenge.
"But the very fact that he's at this stage is nothing short of remarkable and says an awful lot about the man himself."
Former Aston Villa captain Stiliyan Petrov is to resume training with the first team, after more than four years away from football.