To provide a method for controlling the on-line of a tire manufacture component, in which not only dimensional characteristic but also quality of material can be controlled.

Terminals 6, 7 having different electric potential are brought into contact with different points of ≥2 of the tire production component T and current is generated between two points. This current is measured by a measuring equipment 3 and electric resistance of the component between two points is decided. This electric resistance is compared with reference value.