The invention relates to a passing light brightness dead line based on human vision for a headlamp and an HV (Hyper Velocity) point computing method. In the method, the irradiation direction of forward passing light of a motor vehicle which relates to driving safety is detected; and the light intensity distribution situation of lamplight on a screen which is 10 meters away is imaged at a near-distance place by using a lens, an image is analyzed according to the light intensity distribution characteristics of driving light, passing light and a fog lamp defined in GB4599-2007 Automobile Headlamp Light Distribution Performance, and a lamplight irradiation direction is determined, so that miniaturization of an instrument is realized, and the requirement on a place is lowered.