A passive millimeter wave system of this invention is comprised of; human body detector sensors which detect human bodies passing a scanner; passive millimeter wave image sensor modules arranged horizontally or vertically to acquire millimeter wave images radiated from human body in horizontal and vertical axes at certain time intervals; amplifier which amplifies the DC voltage from passive millimeter image sensor modules to a certain level; analog-digital converter which transforms the amplified DC voltage to digital signals; mobility detector which detects movement of human body passing predetermined position to acquire millimeter wave signals from human body; digital signal processor which interlinks and reconstructs signals with the time and position of the object obtained from mobility detector and the signals obtained by passive millimeter image sensor modules; monitor which displays the image of the signals processed with digital signal processor.