The invention discloses an automobile spatial feature point position flexible detection system based on machine vision, and aims at solving the problem of three-dimensional detection of automobile body feature points. The automobile spatial feature point position flexible detection system based on the machine vision is mainly composed of a feature point flexible detection frame (1), a target plate (2), a video camera (3), a video camera protective cover (4) and a video camera support (5). The system acquires target images via the video camera and realizes measurement of any spatial feature points of the whole automobile according to the relation of the vertex of the feature point flexible detection frame (1) and the feature position of the target plate (2) so that the automobile spatial feature point position flexible detection system based on the machine vision is simple in structure, high in detection precision, easy and convenient to operate, easy to install, relatively low in cost and reliable in performance.