In this study, corn was planted under winter wheat-summer corn rotation system in the sand-ginger-black soil area of South Henan for the field experiment, adopting the wheat-corn annual rotation pattern. The fertilizer was set up to six treatments with organic fertilizer replacing different proportions of chemical fertilizer nitrogen in the previous wheat season: T0(0), T20(20%), T40(40%), T60(60%), T80(80%) and T100(100%). Fertilizers were applied normally to all plots in the corn season. The parameters of maize resistance to downy related phenological traits and mechanical indexes were collected at the corn silking stage, soil soluble nitrogen content at the maize pulling stage, silking stage and maturity stage, and yields and their constitutive factors at the maturity stage of maize. The results showed that compared with the T0 treatment, there were no significant changes in plant height, center of gravity height, ear height and coefficient of ear position of spathe stage maize treated with organic fertilizer replacing different proportions of chemical fertilizer nitrogen. The diameter of the 3rd, 4th, 5th internode, the dry mass of the internode, the dry mass of the dry matter per unit of the stem length, the crushing strength and the antiretroviral index were increased. The T60 treatment significantly increased the antiretroviral index of maize stalks. In the maize pulling period, spathe stage and maturity stage, the soil soluble N contents of organic fertilizer replacing different proportions of fertilizer N treatments were increased to different degrees, and all of them were highest in the T60 treatment. The maize yield and 100-grain quality of organic fertilizer replacing fertilizer N treatments were increased, and the maize yield of the T60 treatment was significantly increased by 15.61%. It could be concluded that organic fertilizer forecrop replacement of fertilizer nitrogen could improve the maize resistance and yield of the later crop and the organic fertilizer replacing 60% of fertilizer nitrogen had the optimal effect.