The invention relates to the field of pesticide preparation and discloses an indoxacarb microemulsion and a preparation method of the indoxacarb microemulsion. The indoxacarb microemulsion provided by the invention comprises the following ingredients in percentage by weight (accounting for the total weight of the microemulsion): 1 to 30 percent of indoxacarb, 10 to 20 percent of solvents, 10 to 30 percent of emulsifying agents, 0.5 to 10 percent of cosolvents and the balance water. The indoxacarb microemulsion provided by the invention has the advantages that the cost is low, the preparation process is simple, the package requirement is low, meanwhile, the consumption of organic solvents is reduced, the residue is little, the environment pollution is little, in addition, the prevention effect is higher than that of indoxacarb water dispersible granules, the medication quantity can be reduced, and the indoxacarb microemulsion is suitable for large-area popularization.