Abstract: The study selected the beginning date of ground minimum temperature less than or equal to 0℃as first frost date in autumn of Liaoning province and used first frost date data of 14 stations from 1961 to 2010, to analyze first frost temporal and spatial distribution. The results showed that since mid-late September, first frost occurred from the northwest, northeast to the south of Liaoning, the date of first frost appeared earlier in mountain area than in plain region, came later in coastal area and finally to Dalian area. Along with the time change, the trend of the first frost occurrence date was postponed. Based on the weather chart, the paper discussed the first frost circulation characteristics 24 hours before the frost occurrence, summarized the first frost forecast index, standardized forecast process and provided reference for the real-time forecast