Based on the daily temperature data during January 1951 to April 2007 in Nanjing,the change trends and characteristics of mean temperature,yearly maximum temperature,yearly minimum temperature,cold accumulated temperature and hot accumulated temperature in Nanjing are analyzed.The change of cold winter,warm winter,cool summer,and hot summer are discussed.The results show that the mean temperature tends to rise obviously,especially in spring and winter with the former larger than the latter.The yearly minimum temperature and cold accumulated temperature tend to rise remarkably,and the yearly maximum temperature and hot accumulated temperature tend to descend slightly.In recent 56 years,the all cold winters have appeared before 1980s and the warm winters are frequently observed after 1990s.The spring comes earlier with the time lengthen a little.The length of summer has prolonged for about four pentads.The length of autumn has shortened for about two pentads with starting time about ten days later.The length of winter has shortened for about 3 pentads.