Abstract: The result of the study of plastic films with different color and different ways showed that the amount of maize yield of the half covered was higher than that of the fully covered in case of more rainfall, the amount of maize yield of the black plastic film mulched was higher than white plastic film mulched, and among all the different mulched ways, the amount of the maize yield that was the highest in the field that was mulched with black plastic film half covered, reaching at 2465.88kg/667m2, and at 408.29kg/667m2 higher than that mulched with no plastic film, with an increase of 19.84%.The increase by mulching the filed with black plastic film was significant, and this way could be promoted in large area of semiarid Ulanqab and the surrounding areas with similar climate.