Qiwei Baizhu San was found to have an inhibitory effect on human rotavirus (HRV)at monolayer of MA104 Cells. A 50% reduction in plaque number, a 10(1.86)TCID50 decrease in viral replication index and around 60% inhibition in viral RNA synthesis were observed at concentration of 100 mg/ml. Furthermore, the cytotoxicity of the decoction was low, while its promoting effect on growth and proliferation of the culture cells was observed at the concentrations of 12.5-50 mg/ml. The decoction was also found to have effects in prolonging the survival time of HRV...