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Based on the observation data of frozen soil from 61 meteorological stations in Liaoning Province from 1964 to 2013, by using methods of linear regression, correlation analysis, and comparison of different standard climate periods, the spatial and temporal variations of frozen soil are investigated. The seasonal change of frozen soil, changes of frozen soil depth, beginning dates, and ending dates are analyzed. The results show that frozen soil in Liaoning Province are distributed zonally with latitude; the seasonal variation of frozen soil is significant, freezing appears mainly in October to next May and the freezing area and depth reach the maximum in late winter and early spring; freezing dates gradually postpone from north to South; thawing date and freezing date are just the opposite. Under the background of global warming in the last few decades, the frozen soil shows a degradation in Liaoning. In most areas the annual average temperature and the surface temperature are significantly negatively correlated with the maximum frozen soil depth, which are the most important factors affecting the depth of frozen soil. The maximum depth of frozen soil shows a shallow trend according to the 100cm isobath for different climate periods.