Based on the related data from 1999 to 2003 in Lishui, the correlation analysis of traffic accidents and weather conditions is conducted. The results show that traffic accidents are related to sunshine, rainfall, high temperature, temperature difference, visibility, humidity, snowfall, and wind speed. The traffic accidents occur more likely on high temperature days in summer and on low temperature days in winter, as well as on rainy, snowy, foggy days. The traffic accidents occur more frequently in fine days than cloudy days both in summer and winter, and vice versa in autumn. There are less relatively traffic accidents while the land is frozen up and covered with snow.