Objective To observe the effect of Jianpi Qinghua Decoction on the growth of metronidazole resistant Helicobacter pylori（HP） in vitro and the change of metronidazole content in vivo, and to explore the possible mechanism of Jianpi Qinghua Decoction.Methods Clinical strains of metronidazole resistant HP were selected.In experimental group, 1,1/2,1/4,1/8,1/16,1/32 times of Jianpi Qinghua Decoction was used to intervene the growth and activity of HP.In control group, normal saline was used for comparison.The growth of metronidazole resistant HP in vitro and the change of metronidazole content in bacteria were observed by agar dilution method and ELISA method.Results Antibacterial test in vitro showed that 1,1/2,1/4 times of Jianpi Qinghua Decoction had inhibitory effect on the growth of metronidazole resistant HP,and its minimum inhibitory concentration was 1/4 times of concentration; ELISA Results showed that Jianpi Qinghua Decoction was more effective compared with the control group.The contents of metronidazole in drug-resistant HP in each group were increased significantly, showing a gradient change, and the difference between each group was statistically significant（P<0.05）.Conclusion 1,1/2,1/4 times of Jianpi Qinghua Decoction can inhibit the growth of metronidazole resistant HP.At the same time, different concentrations of Jianpi Qinghua Decoction can change the content of metronidazole in bacteria.The mechanism may be related to the influence of HP efflux pump.