In order to know the effects of selfing on cold resistance and its physiological and biochemical characteristics in winter turnip rape,we comprehensively studied six winter rapeseed varieties in different ways of pollination.Results indicated that:(1)Only the content of MDA raised,SOD,CAT,POD activities and soluble protein,free proline contents were declined compared with open-pollinated.(2)Similarly,lower survival rates of the selfing progenies are investigated in the extremely cold condition of the northwest.Meanwhile,all the indicators measured showed the same trend of increasing,and the most significant variation in CAT activity as well as the pre-cooling and after cooling.These conclusions indicated that self-pollination could cause for depression of biochemical and physiological characterization and wintering rates in winter turnip rape,there by possibly impacting the cold hardiness.So we should avoid geitonogamy which arouses the negative effects in winter turnip rape breeding.