Abstract: In order to find out the soil nutrient supply situation in the Yanjiang Region, establish fertilization index system and scientific formula, improve the comprehensive efficiency of maize and enhance fertilizer use efficiency and sustainable use of soil, the authors evaluated effects of formula fertilization and NPK fertilizer application on the agronomic traits and yield of‘Suyunuo 901’via optimal design of“3414”regression. The results indicated that, the‘Suyunuo 901’was a fertilizer-tolerant variety, the main factors affecting the yield were N fertilizer, followed by P fertilizer, and K fertilizer had little effect on yield. The yield of N3P2K2 combination was highest, while that of N0P0K0 combination was the lowest; the investment of N2P2K3 combination was highest, while that of N2P2K0 combination was the lowest; the input-output ratio of N2P2K3 combination was the lowest, 2:15, while the input-output ratio of N2P2K0 combination was the highest, 1:19. These suggested that the yield could not significantly increase with the fertilizer increasing to a certain extent, but would reduce efficiency.