The invention provides a water
emulsion pesticide system capable of substituting for the traditional
oil emulsion. The
system comprises the following raw materials by weight percent: 0.5-60% of crude
pesticide or
pesticide crude oil, 0.5-5% of
macromolecule emulsifier, 0.5-10% of micromolecule emulsifier, 0-15% of cosolvent, 0-5% of
adjuvant and the balance of deionized water, wherein the
macromolecule emulsifier is an amphiphilic
polymer which is formed by polymerizing a component 1, a component 2 and a component 3 at a
mole ratio of 1:(0.05-0.5):(0-0.5) and is in a micro-crosslinked structure; the
viscosity of the 1% deionized water dispersion of the
polymer is between 100 mPa.s to 10000 mPa.s at PH value of 5-9 and 25 DEG C, and a relative molecular weight of the
polymer is between 0.5million to 20 million; the component 1 is
acrylic acid or acrylic ester with carbon molecular number not more than 36; the component 2 is alkenyl
ammonium chloride with carbon molecular number not more than 25; and the component 3 is allyl
amide with carbon molecular number not more than 5. The water
emulsion pesticide
system provided by the invention enables the crude pesticide with tiny
solubility in water, oil or organic solvents to form the water
emulsion with
low toxicity, high efficiency, and good stability. The invention further provides a preparation method of the water emulsion pesticide.