An apparatus for automatic inspection of printed circuit board assemblies inspects for the correct presence, positioning, and orientation of component parts mounted on a base printed circuit board. In this method for inspection of printed circuit board assemblies, an arithmetic comparison operation is conducted on several color pictures of different colors taken of the base printed circuit board mounted with the component parts; and a distinction is made between parts of the base printed circuit board not occupied by the component parts, and the component parts. Optionally, one of the base printed circuit board and the component parts is tinted in a color of a category selected from the group consisting of the green category, the red category, and the yellow category. The arithmetic comparison operation may be division, or may be subtraction. The base printed circuit board may be coated with a preflux mixed with a fluorescent agent, which may be green; or may be coated with a bonding agent mixed with a fluorescent agent, which again may be green. Illumination may be provided by a light source whose wave length varies from visible blue to ultraviolet. The color pictures may be taken by a color TV camera.