A method and a device for measuring the dimensions of a constant velocity joint. In the method, for example, the cylindrical part of an outer member with a specified offset value is supported on the support part of a dimension measuring device for the outer member. On the other hand, a holding bar is inserted into a recessed part formed in the shaft part of the outer member. In this case, balls installed at the tip of the support part are inserted into the ball grooves of the cylindrical part. In this state, a rotating member is rotated to bring a probe into contact with the inside wall of the cylindrical part. The measurement core of a micro gauge is displaced according to the displacement of the probe, and the amount of the displacement thereof is displayed as the amount of the variation of the needle of the micro gauge.