Abstract: In order to alleviate the effects of heat stress on the production performance of dairy cows and reduce the economic loss, the functional nutrition package against heat stress in dairy cows was prepared. One hundred and twenty healthy Holstein lactating cows were randomly divided into experimental group and control group according to the principles of similar parity, milk yield, lactating days and body condition. Under the conditions of moderate heat stress, the dairy cows in control group were fed with the basal diet, and the dairy cows in experiment group were fed with the basal diet with adding 300 g/（d· head）composite functional nutrition package. The anti-heat stress effects of composite functional nutrition package were observed. The results showed that the unit yield of dairy cows in test group was significantly higher than that in control group （P〈0.05） at the end of the test. Compared with pre-trail period, the average unit yield of dairy cows in control group reduced 2.96 kg/（d, head）and that in test group reduced 1.16 kg/（d· head）. The reduction of unit yield in test group was 1.80 kg/（d· head）lower than that in control group. The increasing amplitude of milk protein in test group was 0.13 percentage points higher than that in control group. The milk fat percentage and dry matter content in test group at the end of the test and on the 10-th day after the test were significantly higher than that in control group （P〈0.05）. The reduction of the feed conversion rate of dairy cows in test group was 0.02 lower than that in control group. The results suggested that functional nutrition package against heat stress could not only alleviate the reduction of milk yield caused by heat stress, but it could also enhance the milk protein content, milk fat percentage, dry matter content and feed conversion rate.