Abstract: To solve problem of uneven fertilizer application by organic fertilizer spreader, an optimization experiment was conducted on organic fertilizer spreader．Experiment used fertilizer transporting speed, driving speed, and fertilizer application volume as experimental factors, lateral and longitudinal fertilizer application uniformity variable coefficient as experimental indicators, 2FG-1.2 horizontal organic fertilizer spreader was used to carry out fertilization experiment．Results showed that lateral and longitudinal fertilizer application uniformity variable coefficient increased first and then decreased with increasing fertilizer speed, when fertilizer transporting speed was 0.1021 m/s, lateral and longitudinal fertilizer application uniformity variable coefficient was the smallest, variable coefficient increased with raised driving speed, and variable coefficient initially decreased and then increased with increasing fertilization application volume, reaching its minimum when the volume was 3 kg/m²．Orthogonal experiment results showed that optimum working parameters of organic fertilizer spreader were as follows: fertilizer transporting speed was 0.1021 m/s, driving speed was 3 km/h, and fertilizer application volume was 3 kg/m², with lateral and longitudinal fertilizer application uniformity variable coefficient were 17.80% and 19.83% respectively．Ranking of factors affecting uniformity of fertilizer application by organic fertilizer spreader was as follows: fertilizer transporting speed, fertilizer application volume, and forward speed．In summary, slowing down driving speed appropriately, increasing fertilizer transporting speed, and reducing fertilizer application volume could improve uniformity of fertilizer application．A reference for research and development of organic fertilizer spreading technology and equipment was provided．