Abstract: Fulvic acid, derived from humic acid, is widely used in foliar fertilizers and functional water-soluble fertilizers at present. Based on its natural properties and structural characteristics, this study used avermectin as a model pesticide to evaluate the feasibility of potassium fulvic acid as a dispersant in the preparation of pesticide suspension concentrate (SC). Wet grinding was adopted during the preparation of abamectin 100 SC with fulvicacidpotassium as dispersant. The grinding efficiency and the stability, under the condition of cold, hot or normal temperature storage, of the preparation were considered as the main indexes to screen the dispersant, wetting agent, thickening agent and other auxiliary agents. The results indicated that in the optimal formula of SC, the mass fraction of fulvic acid potassium addition as dispersant was 3%, the mass fraction of OP-10 as wetting agent was 1%, thickening agent xanthan gum and magnesium aluminosilicate were 0.15% and 0.5%, respectively, the mass fraction of citric acid as pH regulatorcitric acidaddition was 0.02%, and the mass fraction of X60 as defoamer was 0.1%. Among them, fineness (75 μm) ≥ 99%, cold and heat storage stability were qualified. The results from biological activity shown that, when the dosage of abamectin was 0.1 mg/L to 2.5 mg/L, the toxicity of the preparation against southern root-knot nematode Meloidogyne incognita was at the same level with the commercial abamectin SC. In conclusion, fulvic acid potassium can be used as dispersant to prepare abamectin SC with good properties.