Aiming at the problem of inaccurate amount of fertilizer, uneven throwing and lack of fertilizer manure in the process of variable fertilization, the organic variable fertilizer manufaturing machine designed by variable-rate fertilization technology, designed a chain variable precision fertilizer delivery mechanism. By analyzing the movement and stress analysis of fertilizer in the process of organic fertilizer transportation, the equation of the width of the buried scraper, the distance between the two and the angle of inclination of the horseshoe chain were established, and the EDEM simulation analysis was carried out. For the same amount of fertilizer, select the opening size of the gate 5,10,15 mm these three sets of data for field trials. The results showed that the chain variable precision fertilizer delivery mechanism had a good effect on the fertilizer discharge. The maximum relative error between the actual fertilizer amount and the preset fertilizer amount was 7.6% when the power was 14 kW and the gate opening size was 5 mm. Is 10mm, the relative error between the actual fertilizer amount and the pre-applied fertilizer amount is less than 2%, which can better meet the actual production requirements and provide technical support for the research on organic fertilizer spreading machine in our country.