Abstract: Based on the three-decade (1971~2000） meteorological data of the farming-pastoral ecotone in the North of Mount Yin of Inner Mongolia,With the aid of theory of random statistics ,This paper made a preliminary study on the corelationship between sand-storm and rainfall、ground temperature、high wind in the north of Mount Yin of Inner Mongolia ,At the same time,it also made a preliminary analysis on the corelationship between the genesis of sand-storm weather and nature climate.The result reveal：the simultaneous appearance and common action of dryness、rapid rise of ground temperature and high wind is the main reason leading to sandstorms weather in farming-pastoral ecotone of the north side of the Mount Yin.Monthly mean amounts of rainfall of April and May amounts to11.2percent of the annual mean rainfall ; monthly mean high wind days comes up to41.8percent of the annual mean days of high wind in the same period; besides ,the raried range of ground temperature is8.5℃ in this period(April to May） .At the same time ,in this period sandstorm days comes up to85.7percent of the annual mean days of sandstorms .Days of sandstorms represents a direct corelationship with high wind days and ground temperature during in the same period ,and a inverse corelationship with the amounts of rainfall.this paper through discuss the contents mentioned above ,in order to reveal the formation and varied regulation of sand-storm.

Key words: sand-storm, rainfall, ground temperature, high wind, corelationship