Based on meteorological observational data of seven years and the pattern of sanddust weather process affecting Dalian,t he characteristics and forecast model of sanddust invading Dalian were analyze d．The results show that sanddusts in Dalian occurred frequently in spring, si milar to other sites of China. There were four source locations and three transp ort paths of sanddust. The mean relative humidity was very low and the wind di rection was northwest mainly in sanddust weather. Most of the sanddusts move along the northwest paths invading Dalian.The north path corresponds to three w eather patterns, the west path corresponds to other three systems and the northw est path to four systems. Theforecast of sanddust should pay more attention to the sandrising in upstream region, then combine with analyzing the forecast m odelof three transportation paths.