Abstract: By analyzing the beginning, the last frost date and frostless period sequence of Kulun meteorological stations in Tongliao of 53 years （1961-2013）, we explored their variation trends and distribution characteristics using mean, monadic linear regression and Mann-Kendall methods. The results showed that the frostless period of Kulun in the early days advanced constantly; the final days postponed ceaselessly; the days of frostless duration increased continually;the tendency rate of it was 4.7 d/10a.