A human body back-scattering inspection system is disclosed. The system comprises a flying-spot forming unit configured to output beams of X-rays, a plurality of discrete detectors which are arranged vertically along a human body to be inspected, and a controlling unit coupled to the flying-spot forming unit and the plurality of detectors, and configured to generate a control signal to control the flying-spot forming unit and the plurality of detectors to perform a partition synchronous scan on the human body to be inspected vertically. The present disclosure utilizes the geometry property of the human body back-scattering inspection system, and proposes a multiple-point synchronous scan mechanism which largely accelerates the inspection of human body.