Disclosed is a position controller for a tilting head in a machining center. The position controller includes an offset attachment having a body combined to the tilting head and a spherical contact secured to the body, an offset detector built in the machining center such that the offset detector move out into a process area of the machining center and automatically detects a tool offset from a contact point with the spherical contact, a storing unit individually storing first and second tool offsets by respective rotation positions of the tilting head, and an operator generating a transform offset of the first tool offset by a rotational transform and a center error vector from the transform offset and the second tool offset. Accordingly, the center error of the tilting head is automatically detected and corrected in the machining center.