In order to direct a probe having directivity that a received band is widened in accordance with a measurement distance, toward a DUT, shift the received band of the probe in sequence, receive electromagnetic, and measure electromagnetic interference, a plurality of long and short measurement distances between the probe and the DUT are set, and measurement at the long measurement distance and measurement at the short measurement distance are performed plural times. Herein, the measurement at the short measurement distance is performed on a received band where electromagnetic interference is measured by the measurement at the long measurement distance. Thus, measurement of electromagnetic interference can be performed with high accuracy in a short time.