为研制出具有较好稳定性及润湿展布性的高效氟氯氰菊酯水乳剂，选用国内常见乳化剂进行配方筛选，采用激光粒度仪进行粒径分布研究，用视频光学接触角测量仪测定其表面张力（悬滴法）和接触角（座滴法）。结果发现，4种具有较好稳定性的配方其粒径（中位径）在0.8~2.12 μm间，且热贮后有增大现象；药剂表面张力在40~53 mN/m之间，显著低于去离子水(73.66 mN/m)；药剂在苹果叶面上的接触角为46~74度，且在0~60 s内呈显著下降趋势。其中13号配方表面张力最低，与苹果叶面接触角最小，且下降趋势最明显。研究表明4种配方均具有较好的稳定性和润湿性，尤其是13号配方，铺展速度最快，易润湿，宜用于苹果树喷洒。

In order to prepare Beta-Cyfluthrin EW with good stability and wettability, normal complex emulsifier was used to screen formulation, and determine the particle size distribution of formula with laser particle size instrument, and measure the surface tension and contact angle of formula with OCA20 (used Pendant Drop-method and Sessile & Captive Drop-method respectively). 4 kinds of Beta-Cyfluthrin EW formulation with good stability were found, their D50 were around 0.8-2.12 μm, and the particle size increased after heated storage; the surface tension of liquids ranged from 40 to 53 mN/m, significantly lower than those of deionized water (73.66 mN/m); the contact angle on apple leaves of liquids ranged from 46° to 74°, and obviously decreased within 60 S; In all the 4 kinds of formula, the 13# pesticide contained the lowest surface tension and the minimum contact angle when the solutions were dropped on apple leaves, and the contact angle decreased significantly. The research showed that 4 kinds of formula contained good stability and wet ability, and the 13# formula was the optimum formulation, wetting and spreading fast, so it was suitable for apple tree spraying.