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The conventional observation, ECMWF model， and NCEP/NCAR data are used in the diagnostic analysis of the circulation pattern and the frontogenesis function for the longduration, highintensity and widerange frozen weather occurred in January and February 2008. The results show that the continuous frozen disaster was a process of strong frontogenesis resulted from the cold front moving to Guizhou from north, northeast, or northwest, persisted for long time steadily, under the general circulation of two blocking highs over the Ural and Aleutian at the midhigh latitudes in the Northern Hemisphere. The north and south branch fronts were further south and favorite to the cold air moving to the south, so the quasistationary front produced frontogenesis ceaselessly and remained in the western Guizhou. The dynamic mechanisms of causing snowstorms in the eastern Guizhou include upperlevel divergence, lowerlevel convergence, and their responses to strong ascending motion and cyclonic vorticity. The southwest air current in front of Southern Trough and the terrainblocked movement of cold air are important for the emergence and development of the process.