Spray drift is one of the most important indexes evaluating spray quality. Among spray parameters, nozzle type, size and wind speed are those most closely relating to drift. Investigation of their correlative features to drift would provide basic data for parameter optimization. The work involving in this study was the analysis of the correlation between drift and spray parameters by statistic method. Regression was used to weigh the degree of spray variables affecting drift. The study indicated that nozzle type, nozzle size and wind speed were all strong factors affecting drift, but wind was the strongest one, nozzle type was next and then was the nozzle size.