"The future of this football club is not at this stadium and everyone accepts that is a fundamental point," Scally told the Kent Messenger.
"If I can't achieve a new stadium, I must consider my own personal future, because there's not much more to be achieved here, other than what can be achieved in a small stadium."
Scally took over at the Gills in the summer of 1995 when the club was in administration, buying the club for £1.
He restructured the club and helped take it forward into the most successful era in its history, with an FA Cup quarter-final and two Wembley play-off final appearances, culminating in the club's promotion to the Championship, the first time Gillingham had reached English football's second tier.
However, the massive overspend on the redevelopment of Priestfield has left the club in financial ruin, and with debts thought to be in excess of £11m to the bank, with other debts thought to be owed to the inland revenue and other creditors, it is unknown how long the club's creditors will be prepared to allow the debts to remain.
Scally has repeatedly stated that the club must move from Priestfield if it is to move forward, but it seems that with his latest statement, the promised progress seems not to have materialised.
With the club deep in debt, and Scally now calling his own future at the club into question, it places a huge question mark over the football club.