A measuring method of a chamfered hole diameter using a contact-type position measuring device, said contact-type measuring device comprising: a straight hole diameter measuring probe adapted to measure a diameter of a straight hole which extends in an axis direction which is a straight hole direction; and a chamfered hole diameter measuring probe adapted to measure a diameter of a chamfered hole, the method comprising the steps of: measuring a diameter of a straight hole by moving the straight hole diameter measuring probe in a radius direction along a X-axis direction and make the straight hole diameter measuring probe contact an internal peripheral surface of the straight hole, and computing a center (C') of a movement amount in the X-axis direction, and moving the straight hole diameter measuring probe in a radius direction along a Y-axis direction, perpendicular to the X-axis direction, in a manner of going through the center (C') of a movement amount in the X-axis direction, and computing a center of the straight hole by the measured diameter of the straight hole; moving a chamfered hole diameter measuring probe to be aligned with the computed center of the straight hole; and measuring the chamfered hole diameter by moving the chamfered hole diameter measuring probe in a straight hole direction and contacting an internal peripheral surface of the chamfered hole, so as to measure a stroke amount, the diameter of the chamfered hole being computed based on the measured stroke amount. a straight hole diameter measuring probe adapted to measure a diameter of a straight hole which extends in an axis direction which is a straight hole direction; and a chamfered hole diameter measuring probe adapted to measure a diameter of a chamfered hole, measuring a diameter of a straight hole by moving the straight hole diameter measuring probe in a radius direction along a X-axis direction and make the straight hole diameter measuring probe contact an internal peripheral surface of the straight hole, and computing a center (C') of a movement amount in the X-axis direction, and moving the straight hole diameter measuring probe in a radius direction along a Y-axis direction, perpendicular to the X-axis direction, in a manner of going through the center (C') of a movement amount in the X-axis direction, and moving the straight hole diameter measuring probe in a radius direction along a X-axis direction and make the straight hole diameter measuring probe contact an internal peripheral surface of the straight hole, and computing a center (C') of a movement amount in the X-axis direction, and moving the straight hole diameter measuring probe in a radius direction along a Y-axis direction, perpendicular to the X-axis direction, in a manner of going through the center (C') of a movement amount in the X-axis direction, and computing a center of the straight hole by the measured diameter of the straight hole; moving a chamfered hole diameter measuring probe to be aligned with the computed center of the straight hole; and measuring the chamfered hole diameter by moving the chamfered hole diameter measuring probe in a straight hole direction and contacting an internal peripheral surface of the chamfered hole, so as to measure a stroke amount, the diameter of the chamfered hole being computed based on the measured stroke amount.