The melt blown composite material after electrostatic electret treatment has the characteristics of low initial resistance, large dust holding capacity and high filtration efficiency when it is used for air filtration [under the flow rate of 32L / min, the filtration efficiency of 0.3um particle size can reach 99.9%, and the resistance is only 117.7pa (12mm water column)], which is widely used for air purification treatment in electronic manufacturing, food, material, chemical industry, airport,