The invention relates to rail transportation, and discloses a downhill automatic driving method for a heavy-load train based on movement blocking. The downhill automatic driving method comprises the steps that whether the heavy-load train is braked or not is judged; when the heavy-load train is not braked, whether a slope equivalent accelerated speed exceeds a maximum decelerated speed of electric braking is judged; when the slope equivalent accelerated speed does not exceed the maximum decelerated speed of the electric braking, whether a heavy-load train speed is higher than an early warning recommended speed is judged; when the heavy-load train speed exceeds the early warning recommended speed, a coasting instruction is output to guarantee that the heavy-load train does not accelerate. According to the downhill automatic driving method for the heavy-load train based on the movement blocking, the heavy-load train cannot brake again in sufficient time, and high efficiency running of the heavy-load train and safety of automatic driving are guaranteed.