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

CONSTITUTION: An infrared camera 1 is put on the center of a sample hold carrier 2 and an infrared image of a soldered print base plate 4 on one of steps is set to be measured. The image data is held in a unit 3 having an image memory and a plurality of image data for front and back faces are latched for a print base plate 4. By forming images of difference and ratio of the two image data with different temperatures, a soldering inspection device detectable of abnormality relatively easily and with high probability is realized.