To solve a problem wherein the total guarantee for connecting conditions of a connector pin is not possible since confirmation of a contact load between a connector pin and an insertion hole of a substrate is made by destruction inspection up to now.

A connecting condition inspection device for a press-fitted pin includes an ultrasonic wave transmitter 21 and a vibrator 11 for giving ultrasonic vibration to the connector pin 2 inserted into a connection hole 1a, a first receiver 22 for receiving a reflected wave in the connector pin 2, a second receiver 23 for receiving a transmitted wave from the connector pin 2, and a determination machine 25 for carrying out at least one of comparison between a standard reflected-wave waveform and a received reflected-wave waveform in giving the ultrasonic vibration to the connector pin 2 as an inspection target when giving the ultrasonic vibration to the connector pin 2 at a superior connection condition and comparison between a standard transmitted wave waveform and a received transmitted wave waveform in giving the ultrasonic vibration to the connector pin 2 as an inspection target when giving the ultrasonic vibration to the connector pin 2 at the superior connection condition and determining quality of the connection condition to the connection hole 1a of the connector pin 2.