Abstract: In order to study the effect of cold stress on the physiological indexes and antioxidant function between Kerqin cattle and crossbreed Kerqin cattle, 20 healthy Kerqin cattle and Kerqin crossbred cattle with similar height, weight and parity were selected as research objects. The experiment was divided into two phases: cold stress（December 15-21,2019） and non-cold stress（April 11-17,2020）. Respiration rate, rectal temperature, the activity of superoxide dismutase（SOD） and glutathione peroxidase（GSH-Px）, malondialdehyde（MDA） content and total antioxidant capacity（T-AOC） in two breeds of cattle were determined on the 7 th day of the experiment. The difference of respiratory rate, rectal temperature and antioxidant capacity in two breeds of cattle was analyzed under cold stress and non-cold stress. The experiment results were as follow: the respiratory rate and rectal temperature in cold stress period were significantly lower than those in non-cold stress period（P＜0.05）; in non-cold stress period, SOD activity in the serum was significantly higher than that in cold stress period（P＜0.01）, and the content of MDA was significantly lower than that in cold stress period（P＜0.01）. There was no significant difference in T-AOC between non-cold stress period and cold stress period（P＞0.05）. There was no significant difference in serum GSH-Px activity of crossbred Kerqin cattle between non-cold stress period and cold stress period（P＞0.05）, but the serum GSH-Px activity of Kerqin cattle in the cold stress period was significantly lower than that in the non-cold stress period（P＜0.01）. Under non-cold stress, there was no significant difference in respiration rate, rectal temperature, the activities of SOD and GSH-Px, MDA content and T-AOC in two breeds of cattle. Under cold stress, rectal temperature of crossbred Kerqin cattle was significantly higher than that of Kerqin cattle（P＜0.05）; the respiration rate was not significantly changed（P＞0.05）; serum SOD activity was significantly increased（P＜ 0.05）; GSH-Px activity was significantly higher than that of Kerqin cattle（P＜ 0.01）, MDA content was significantly decreased（P＜ 0.01）, and T-AOC had an increasing trend（P＞0.05）. The results indicated that the cold stress affected different breeds of cattle, and the crossed Kerqin cattle had better thermoregulatory capacity and antioxidant function and could better adapt to the cold weather of Inner Mongolia.