Abstract: A method and apparatus for inspecting a solder joint by an X-ray fluoroscopic image in which an X-ray is irradiated on an object to be inspected located by a specimen stage and having a lead of an electronic part soldered to a substrate to detect an X-ray fluoroscopic image signal, a position of a lead in a tip direction is obtained by a distribution of projection with said X-ray fluoroscopic image signal projected in a lead row direction, a position of a lead in a row direction is obtained by a distribution of projection with said X-ray fluoroscopic image projected in a lead tip direction to extract a position of a solder joint as an object to be inspected, and said X-ray fluoroscopic image is evaluated every solder joint in accordance with the postion information to effect a defect detection.