To accurately inspect printed circuit boards in a general-purpose manner, regardless of the shape of the printed circuit boards or the surface-mounted components.

A method for inspecting the printed circuit boards includes steps of irradiating the printed circuit board 1, having a conductor pattern 2 covered with flux 4, a surface-mounted component 3, and an external connection terminal 3a with a near-infrared light 5a permeating the flux 4 from infrared lighting 5; photographing a reflected light thereof with an infrared imaged detection device 6, capable of detecting the near-infrared light 5a; inputting the images of the underlying conductor pattern 2, the surface-mounted component 3, and the external connection terminal 3a to an image processing section 7, without being disturbed by the surface flux 4; and determining the position or the defects of the conductor pattern 2, the surface-mounted component 3, and the external connection terminal 3a on the printed circuit board 1. The method eliminates the effects of the flux 4 so as not to place restrictions on a lighting direction or the attitude of the printed circuit board 11, enabling general-purpose and accurate inspection of the printed circuit board 11.