Objective: To study the antibacterial action in vitro of compound cortex dictamni lotion. Method: The test-bacterial isolated from cl inic was used, minimal inhibitory concentration (MIC) and minimal bactercidal concentrati on (MBC) of compound cortex dictamni lotion were observed. Result: MIC and MBC of compound cortex dictamni lotion were 12.5% and 25.0% (ml/ ml) to Candida, 12.5% and 25.0%(ml/ml) to S.aureus, 6.25% and 6.2 5%(ml/ml) to Ps.aeruginosa. Conclusion: Compound cortex dictamni lotion is inhibit...