PURPOSE: To enable inspecting the abnormality of soldering state with a soldering inspection device without sending electricity, relatively easily and with high probability.

CONSTITUTION: Thermal infrared camera 1A and 1B sensing to two ranges of 10μm band and shorter wave length band are set and a thermal image of a soldered print base plate 6 higher than the ambient temperature within the temperature range of not harming solder is taken by referring the thermal image of a standard object 7 at the ambient temperature. By forming and indicating the thermal infrared images of difference and ratio images of the two wave length band for the difference image using a processing unit, a soldering abnormality can be detected relatively easily and with high probability without sending electricity.