Abstract: Applying data of daily lowest ground temperature less than 0 ℃ through March to May of 17 meteorological stations in Linfen District,Shanxi Province,over 30 years from 1981—2010,we have done a research on determining the spring frost and the last frost date.Using linear trend analysis method,the interannual variation of the spring frost in Linfen District has been analyzed.Meanwhile the Mann-Kendall discontinuity analysis method has been used to test mutations in the sequence of the end dates of frost and the contour maps of the real part of wavelet transformation coefficients and wavelet variance maps have been depicted by conducting the continuous wavelet transform on the end frost dates.The results show that firstly the end dates of frost advance obviously in the north,west and middle parts of Linfen District,the south part presents a slow advance trend,while the east part has the slow delay trend.The climate tendency rates of frost intensity in each region vary,but not obvious.Secondly,the mutation year in eastern,central and southern parts of Linfen appears in 2007,while the mutation year in western Linfen is 1990,and in northern Linfen the mutation occurred in 1997.The trend after the mutation is advancing in east and south while delaying in west and north.Each region has the main cycle of 7 a.The sub cycle,in addition to the central region of Linfen district for 8 a,is 11 a for the other regions.The above conclusions provide a theoretical basis for the prediction of frost in Linfen,which is also of great significance for guiding the local agricultural production.