To observe and evaluate the effect of Xinjia Dayuan Powder on the formation of the number of bacteria in the biofilm of methicillin-resistant Staphylococcus aureus standard strains by using The XTT method and microfluidic system Methods:1)The XTT method was used to observe the effects of the blank group,vancomycin group and Xinjia Dayuan Powder group(water extraction,alcohol extraction)on the living bacteria in the MRSA standard strain biofilm at the mature stage.2)We inoculated MRSA bacteria in the Bioflux200 system to the observation area.After the bacterial biofilm was formed,we added a certain concentration of Xinjia Dayuan Powder water extract,alcohol extract,solvent control group,blank group and vancomycin to each inlet hole,and then under the action of 0.5 dyne shearing force,they were continuously cultured for 30 h to observe the formation of biofilm in each group.Results:1)XTT method showed that Xinjia Dayuan Powder can significantly reduce the number of viable bacteria in the MRSA biofilm during the formation and maturation phase.2)The area of biofilm formation in the water extract and alcohol extract group of the 2 concentrations of Xinjia Dayuan Powder decreased significantly,the area of biofilm formation in the blank group and solvent control group increased,and the area of biofilm formation in the vancomycin group decreased compared with the previous one,but not significantly different than the 2 groups of Xinjiada Yuan Powder.Conclusion:Xinjia Dayuan Powder can reduce the number of bacteria in MRSA biofilm.In the flowing state,a certain concentration of Xinjia dayuan Powder can inhibit the formation of MRSA biofilm under the action of shearing force; Bioflux200 can be used to evaluate the curative effect of antibacterial Chinese medicine.