To investigate the mechanism of the sandstorm,based on the correlation analysis, the establishment of the gale modified index, trends analysis, and moving correlation method, the correlation between Sandstorm in North China and meteorological elements is conducted,utilizing surface observing data from 7 meteorological stations in China during the period of 1954—2000,including monthly rainfall, gale dates, mean monthly temperature and sandstorm frequency. The results show that the correlation coefficient between the sandstorm frequency and rainfall at the same period is negative, but the correlation coefficient between the sandstorm frequency and the previous year rainfall is not obvious, and their extrema are corresponding. The correlation between the sandstorm and gale frequency and gale modified index is positive, the comparison shows that the gale modified index can well indicate the rule of sandstorm. The correlation between it and the previous winter temperature is negative, after eliminated the trend, the negative correlation does not exist, so their correlation is due to their trend. Through 20 years moving correlation analysis, from which the 6 stations show the same trendency, so it shows that their correlation is related to the degree of underlying surface desertification.