In view of the problems of low fertilization efficiency of conventional fertilizer applicators, easy clogging of organic fertilizer, and difficulty in mixing organic fertilizer and chemical fertilizer, a hanging deep watermelon organic fertilizer applicator is designed, which realizes a single operation process to complete the opening of fertilizer ditch and chemical fertilizer. The mechanized duplex operation of organic fertilizer mixed deep application and trench soil backfilling. Through the combined design of the crushing knife group and the auger fertilizer discharger, the pulverization and uniform transportation of organic fertilizers are realized the mechanized mixing and deep application of organic fertilizers/chemical fertilizers are realized, and precise control can be performed according to the nutrient requirements of watermelon. The ratio of organic and chemical fertilizers. The performance test shows that the working parts of the watermelon organic fertilizer deep applicator run stably. The field test shows that the fertilizer particles are evenly distributed, among which the distribution stability coefficient of organic fertilizer is ≥91.65%, the stability coefficient of chemical fertilizer distribution is ≥93.28%, and the distribution of mixed fertilizer The stability coefficient is ≥ 93. 70%, which meets the production requirements of watermelon.