In order to study the relationship between the atomization properties and dynamic surface tension(DST) of pesticide surfactants aqueous solutions, the median volume diameter （D50） of agriculture flat-fan nozzle were measured, with the particular emphasis on the effects of different nozzles and pressures. The results showed that the D50 was correlated linearly with γ0.023; the D50 increased resulted from DST with the increase of the nozzle type under the same pressure; with the increase of the pressure, the D50 decreased for the same nozzle.