In order to study the law of soil water and fertilizer transport under the corn full film double ridge planting mode in northwest arid area, the HYDRUS-2D/3D model was used to numerically simulate the law of soil water and fertilizer transport and root response of corn full film double ridge planting mode in Dingxi City, Gansu Province, the distribution law of soil water content and seed fertilizer concentration in the ridge under the full film double ridge planting mode was analyzed, and observation points at reasonable sowing depths were set to characterize the interaction law of soil water content, nitrogen phosphorus and migration of potassium, water and fertilizer. The simulation results showed that the circular lateral infiltration of soil water and fertilizer occurred at the infiltration holes and seed holes of full film double ridge and furrow, in which the fluctuation range of soil moisture content was 15.20%~17.12%, the concentration value of nitrogen fertilizer transformation in the ridge and furrow tended to be 15.38mg/L, the concentration value of phosphorus fertilizer transformation tended to be 5.15mg/L, and the concentration value of potassium fertilizer transformation tended to be 12.21mg/L. Water and fertilizer were mainly concentrated in the ridge and furrow, which ensured the water and fertilizer demand at the seedling stage. The simulation of root water uptake and water and fertilizer transport showed that the soil water and fertilizer conditions under the full film double ridge and ditch mode met the needs of maize seedling emergence. The research model and results would provide a theoretical basis for the optimization and improvement of maize full film double ridge and furrow agronomic technology.