To provide an on-vehicle electronic control unit and inspection device therefor which enable reduction of the work man-days and prevention of working errors, and consequently to enhance the quality of inspection.

The ECU 20 is provided with an inspection result memory 25 for storing inspection results obtained by three kinds of temperature inspections. As a result of this, the inspection results can be read from the result memory 25 of the ECU 20 as occasion arises, since the inspection results by the temperature inspections are stored in the result memory 25 of the ECU 20. Since the pass mark or the like to the effect that the ECU 20 has passed the temperature inspections is not required to be stamped on the ECU 20 as a result, no workers who perform marking work are required, and visual confirmation of a pass mark is not required either. Accordingly, work man-days can be reduced and working errors can be prevented. As a result, the inspection quality can be enhanced.