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Based on data from 84 observation stations in Guizhou Province and NCEP/NCAR reanalysis, a comprehensive comparative analysis of two extreme freezing rains that occurred in 2008 and 2011 are made through temperature declining amplitudes, affected stations, sea surface temperature patterns and circulation patterns. The results show that: the Eastern type of La Nina with medium intensity provided a favourable condition for the development of freezing rain in two cases. Besides, there were some similar circulation patterns in two cases, such as positive geopotential height anomalies over West Asia and negative geopotential height over East Asia at 500 hPa, stable maintenance of shear line at 850 hPa, southwest jet at 700 hPa, temperature inversion layer and melting layer between 800 to 600 hPa, which were conducive to the formation of freezing rain. However, compared to the case in 2011, it could be observed that the shear line located further north, southwest jet at 850 hPa and temperature inversion layer had stronger intensity and larger area, colder temperature advection and thicker melting layer with longer duration and higher centre temperature from the case in 2008, which could possibly result in more significant influence from freezing rains in 2008.