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Based on the conventional observational, automatic meteorological observing station, and the NCEP 1°×1° reanalyzed data, two extreme snowstorms in Shandong on 28 February in 2010 (“2〖DK〗·28” for short) and 19 April in 2013 (“4〖DK〗·19”) are comparatively analyzed. The results show that: (1) Both snowstorms were caused by the 500 hPa upperlevel trough, lowlevel southwest jet, and shear line at 700 hPa. The differences are that the cold air came from northeast before the “228” snowstorm and forced the warm and wet air to climb, which played an active role, while there were northeast winds and a “cold pad” formed before the “4〖DK〗·19”snowstorm, and the warm air clam climbed along the pad, in which the cold air played a passive role. (2) There was an obvious energy frontal zone, inversion layer, and thick wet layer in both snowstorms. The vertical helicity has a distribution characteristic of positive at lower levels and negative at upper levels. The snowstorm area was located in the large water vapor flux area near the left side of the vapor flux divergence center. The difference lied in: comparing with the “4〖DK〗·19”snowstorm, the “2〖DK〗·28”snowstorm has a higher rising height of convergence, stronger ascending motion, and more profound and unstable stratification.