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Based on the daily temperature records of 76 stations in Hunan province from 1961 to 2014, the four seasons’ statuses including their start dates, lasting period etc., analyzed in line with the industry standards of meteorology. Their variations are also studied through the statistic methods such as wavelet analysis, climatic trend analysis and so on. The results show that the start dates of spring and summer changed clearly with the latitudes, which delayed from south to north in spring and from southeast to northwest in summer; the average numbers of days in each of four seasons in Hunan were 77 (spring), 138 (summer), 66 (autumn) and 85 (winter), respectively. Over the years, the tendency rate of summer duration change was 277 days per 10 years, with the consistency increased. There were two highvalue centers in the north and south. The winter tendency rate was -293 days per 10 years and the consistency reduced, with the low altitude areas reduced more obviously. From the 1960s to the 2010s, the interdecadal fluctuation of summer duration was most obvious, and after the 1970s, the number of summer days increased continuously. The number of winter days decreased sharply since the 1990s, and the trend continued.