To provide a method and apparatus for judging a timing of replacing a bladder for tire vulcanization, in which the timing of replacing the bladder is surly judged by appropriately grasping a state of the bladder causing malfunctioning molding of a tire dispensing with a process for inspecting the presence or absence of bad molding carried out after replacing the bladder and a waste of productive resources.

The method comprises calculating from a picked-up image of an inner periphery of a tire a degree of scattering of a concavo-convexo state of a region except for a convex part attached to the inner periphery of the tire by a bladder for vulcanization when molding the tire, comparing the degree of scattering with a predetermined threshold value, and judging that it's a timing of replacing the bladder for vulcanization if the degree of scattering is larger than the threshold value.