This paper aims at probing the effect of low temperature stress at booting stage of winter wheat on its physiological and biochemical characteristics and grain yield.‘Xiaoyan 22’ and other 4 cultivars were taken as tested materials.The superoxide dismutase (SOD) activity,peroxidase (POD) activity,catalase (CAT) activity,relative conductivity,MDA content,the soluble sugar content,the soluble protein content and the proline content were investigated after different time treatments (0 h,24 h,48 h),and the grain yield of 5 tested cultivars were also investigated.The results showed that:(1)After being chilled for 24 and another 24 hours,compared with the contrast,the SOD activity,POD activity,CAT activity,MDA content,relative conductivity,soluble sugar and proline contents increased significantly in the both chilled leaves;while the soluble protein content decreased significantly.(2)Low temperature stress at booting stage significantly decreased grain yield and the number of grain per ear,but the effects on the number of spike and 1000-grain weight was less significant.(3)Based on fuzzy mathematics method,‘Xiaoyan 22’,‘Aikang 58’ and ‘Xinong 509’ belong to high cold resistance group,and the other 2 cultivars,‘Zhengmai 9023’ and ‘Zhengmai 366’,belong to low cold resistance group.Which is accordance with the production in this experiment.Compared with low resistance wheat cultivars,the high cold resistance wheat cultivars showed higher antioxidation enzymes,lower negative effects on the cellular membranes,and higher osmotic adjustment,which may be the major physiological traits to have a relatively higher production after the low temperature stress.