The sprayed droplets were sampled with oil cell and the droplet sizes were measured by use of computer vision technique. The brand new droplet sizing technique was developed based on the computer vision. In comparison with the results measured by using PMS laser imaging technique, they had very close droplet sizes and the volume percentage of droplets with less than 150 micrometers. In comparison with the data provided by Spraying Systems Co. Ltd, they had almost the same VMD data.