The invention relates to a method for detecting a vehicle near a rail. The method comprises the following step: detecting by adopting a system used for detecting the vehicle near the rail. Aiming at solving the technical problem that the vehicle near the rail is difficult to be detected accurately when approaching in the prior art, the technical scheme of executing corresponding filtering processing on a high-quality filtered image originated from a scene around a railway to obtain a corresponding de-noised image, carrying out dynamic range reinforcement treatment on the de-noised image to obtain a corresponding high-dynamic-range image, forming pixel points with the pixel values between a vehicle upper limit gray threshold and a vehicle lower limit gray threshold in the high-dynamic-rangeimage into a vehicle subimage, and sending out a vehicle approaching signal when the area of the vehicle subimage is larger thanor equal to a preset area threshold; and carrying out fatigue early warning operation when the current fatigue of a metal connector on the railway is largerthanor equal to a preset fatigue threshold, so that the technical problem is solved.