Abstract: [Objective]In order to study the effect of traditional Chinese medicine compound on the production performance and rumen fermentation parameters of lactating cows.[Method]40 lactating cows were randomly divided into four groups in this experiment,namely control group,experimental group I,II and III,100 g/d,200 g/d and 300 g/d of traditional Chinese medicine compound were added to the basal diet in experimental groups. After the 7-day pre-trial period,the lactating cows were continuously fed for 30 days,and the production performance indicators and rumen fermentation parameters were detected at the end of the experimental period. [Result]Compared with the control group,the average daily gain and average daily feed intake of test groups I,II and III were significantly increased（P<0.05）,and the feed-to-weight ratio was significantly decreased（P<0.05）. The milk production,4% standard milk yield and milk fat in the produced milk were significantly increased.（P<0.05）and the number of somatic cells was significantly decreased. （P<0.05） The pH of dairy cow rumen fluid was significantly decreased（P<0.05）,and the total volatile fatty acids were significantly increased（P<0.05）.[Conclusion]The traditional Chinese medicine compound improved the production performance of lactating cows and improved the rumen fermentation.

Key words: traditional Chinese medicine compound, lactating dairy cows, production performance, rumen fermentation parameters