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China's oilseed rape cultivation area is among the highest in the world, with about 6.2 million hectares planted year-round, and 85% concentrated in the Yangtze River Basin rice and oil rotation area, providing an important guarantee for the safety of Chinas edible oil supply. Precise and reasonable fertilization is an important way to reduce agricultural production costs, improve the quality and safety of agricultural products and reduce the pressure of environmental pollution. The Central Committee of the Communist Party of China and the State Council pointed out that supporting oilseed rape production in the Yangtze River Basin has presented new challenges and opportunities for chemical fertilizer reduction and precision application during oilseed rape production. On the basis of the spiral disturbance cone centrifugal fertilizer discharger designed in the previous stage, the problem of poor fertilizer discharge performance of the spiral cone centrifugal fertilizer discharger, unclear influence law of each parameter on fertilizer discharge performance and little research on related theories and analytical models was addressed. A model of the movement of granular fertilizer in the fertilizer discharger was established and the main structural parameters and ranges affecting the performance of the fertilizer discharger were determined through theoretical analysis. The EDEM discrete element simulation software was used to carry out a quadratic regression orthogonal rotation combination test. In order to verify the performance of the optimized fertilizer discharger, a fertilizer discharge calibration and performance verification test was carried out based on the optimal combination of parameters of the fertilizer discharger. The test results showed that the variation coefficient of stability of fertilizer discharge volume and the variation coefficient of consistency of fertilizer discharge volume in each row was decreased, with the variation coefficient of stability of the fertilizer discharge volume was no more than 3.12% and the variation coefficient of the consistency of fertilizer discharge volume in each row was no more than 5.29%. The variation coefficient of consistency of fertilizer discharge volume was decreased with the increase of speed of fertilizer discharger, the difference between the rows was small, and variation coefficient of the consistency of fertilizer discharge volume of the rows was no more than 2.05%, indicating that the fertilizer discharger was stable and met the requirements of fertilizer discharge quality. There was an obvious linear relationship between the row fertilizer supply rate and the rotational speed of the fertilizer rower, which provided theoretical support for variable fertilizer application at a later stage. Field tests showed that the variation coefficient of the stability of fertilizer discharge volume was no more than 4.57%, the variation coefficient of the consistency of fertilizer discharge volume in each row was no more than 6.98% and the variation coefficient of the consistency of peer discharge volume was no more than 3.56%, meeting the requirements of the industry standard. The research result can provide a theoretical reference for improving the operational quality of fertilizer dischargers and design of fertilizer dischargers.