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Taking Cangzhon of Hebie Province as an example, based on the meteorological data from 1970 to 2005, an analysis is made of meteorological factors affecting greenhouse vegetables in winter, such as extreme minimum air temperature, winter average temperature, severe temperature drop, fog, scant sunlight, gale, heavy snow and so on. The results show that extreme low temperature and winter average temperature had an increasing trend; fog had a fluctuational decreasing trend; gale decreased obviously. These are beneficial to greenhouse vegetables. The scant sunlight exhibited an increased tend, especially after the 1990s, which is unfavorable to greenhouse vegetables. Severe temperature drop and heavy snow tended to change abnormally. In view of these variation characteristics of meteorological factors, some suggestions are presented, such as increasing light intensity, preserving heat, and strengthening capability to defense against extreme weather and climate events.