To solve the problem wherein a bad product passes the inspection of spot welding because the inspection of spot welding after spot welding work is performed heretofore by worker's sampling inspection, and there is a numerical value data comparing method by CAD but work is difficult.

This automatic inspection system of spot welding is constituted so that the positions of the whole number of the spot welding points SP of a perfect inspection target becoming a sample preliminarily subjected to spot welding S according to an official spotting indication chart are photographed by a movie camera 1 to record these taken images on an image processing unit 5, and the positions of the whole number of the spot welding points Sn of an inspection target B actually becoming a product are photographed by the movie camera 1 to record these taken images on the image processing unit 5, and these images Sn are compared with the preliminarily recorded images SP of the whole number of the spot welding points of the perfect inspection target object to automatically determine an inspection result.