Objective: To investigate the in vitro effects of Radix et Rhizoma Dispori extracts on bacteria and fungi. Method: The effects on bacteria and fungi of Radix et Rhizoma Dispori extracts were measured by inhibition zone diameters. The minimal inhibitory concentrations (MIC) and the minimum bactericidal concentration (MBC) of Radix et Rhizoma Dispori extract was determined by micro-liquid dilution method. Result: Radix et Rhizoma Dispori extracts

except for the water layer

have apparent inhibitory effect to Staphylococcus aureus

Escherichia coli

Pseudomonas aeruginosa and Klebsiella pneumonia. The 95% alcohol extract (1:40) and the 95% alcohol elution part (1:40) could kill S. aureus. All extracts of Radix et Rhizoma Dispori showed no inhibitory effect to Candida albicans and Cryptococcus neoformans. Conclusion: Some extracts of Radix et Rhizoma Dispori have bacteriostatic activities

but no inhibitory effect to single-celled fungi in vitro.