It puts to an end the speculation that he would leave Celtic when a suitable offer came in for him.
Rumours that he was said to be leaving seemed believable when Petrov was dropped from the squad against Dundee United at Tannadice last year.
But Martin O'Neill is said to 'absoloutley delighted' with the new deal.
Petrov has not been having the greatest of seasons so far, but hopefully this will boost him to show us all what he can do.