[Objective] The variation characteristics of sandstorm weather frequency in Western Inner Mongolia Autonomous Region in the recent 54 years were studied in order to provide theoretical basis for its scientific prediction and prevention and treatment.[Methods] Through the methods of linear regression, 5-year sliding average, wavelet analysis, moving t test and Mann-Kendall, the changing trend, periodicity and mutagenicity of sandstorm day number of 24 meteorological stations in Western Inner Mongolia Autonomous Region were analyzed.[Results] ① In the recent 54 years, the frequency of sandstorm weather could be divided into high frequency period(1960-1975), rapid attenuation period(1976-1992) and low frequency period(1993-2013). The frequency of dust occurrence was 17, 9, 4 days per year, there were 31, 22, 13 years long periods and 5, 8, 1.5 years short cycles. ② There was an obvious mutation in the frequency of sandstorm around 1986. The linear decrement rate of 1976-1986 was 0.76 day per years, that of 1987-1992 was 1.4 days per years.[Conclusion] In the recent 54 years, the change of sandstorm day number in Western Inner Mongolia Autonomous Region showed a fluctuating trend, and there were obvious cyclical and mutagenic characteristics.