The invention discloses an environment-friendly water-based insect aerosol and a preparation method of the environment-friendly water-based insect aerosol, wherein DME serves as propellant for filling. The prepared environment-friendly water-based insect aerosol is composed of quasi pyrethrin-class insecticidal active compounds, water, the propellant and the like, and an aerosol tank is filled with the quasi pyrethrin-class insecticidal active compounds, the water, the propellant and the like. The insecticidal active compounds are the compound of quasi pyrethrin-class insecticides, and the mass ratio of the insecticidal active compounds is 0.33-0.60%; the aerosol further comprises, by mass, 1-4% of surface active agents, 0.01-0.12% of corrosion inhibition anti-corrosion agents, 0.1-0.28% of penetrating agents, 6-18% of solubilizing agents, a proper number of complexing agents, a proper number of wetting agents, a proper number of defoaming agents, excipient and 0.01-0.026% of essences, wherein the excipient is purified water or deionized water, and the sum of the mass percents of the raw materials and the auxiliary materials is 100%. The liquid contained in the environment-friendly water-based insect aerosol is homogeneous and transparent. The retention period is more than four years. Mosquitoes, flies, cockroaches, ants, white ants, mites, lice, bugs, ticks, fleas and the like are killed in an environment-friendly mode, and the repelling function and the function of the long lasting period are achieved. The aerosol is an efficient and high-cost-performance product. The aerosol does not exist in domestic and foreign markets.