OBJECTIVE: To study the effects of bupleurum root, scutellaria root and baked licorice respectively, on viral myocarditis caused by coxsackievirus B3 (CVB3) in mice. METHODS: The viral myocarditis model was established by injecting CVB3 in 100 Balb/C mice. Normal saline (served as the control group), bupleurum root, scutellaria root and baked licorice were administrated by intragastric route in 25 mice respectively, with the dosage of 0.5 ml , once daily for 2 weeks. The pathologic changes in myocardium of mice were evaluated with the routine histopathological method. RESULTS: The pathology scores of myocardium on the 5th, 7th and 10th days after treatment in the bupleurum root group ( 1.33 ± 0.82 , 1.60 ± 0.63 and 1.87 ± 0.74 , respectively) were significantly lower than those of the controls ( 2.22 ± 1.37 , 3.27 ± 0.96 and 2.60 ± 1.06 , respectively) (P< 0.05 or 0.01 ). On the 5th and 7th days after the treatment with baked licorice, there were significant differences in the pathology scores of mycocardium between the baked licorice group (1.26±0.88 and 1.80±0.68) and the control group (P< 0.05 or 0.01 ). Scutellaria root took effects later. The pathology scores of myocardium in the scutellaria root group significantly decreased on day 14 and day 21 after treatment compared with those of the control group ( 1.53 ± 0.74 vs 2.33 ± 0.98 and 0.80 ± 0.56 vs 1.40 ± 0.83 , respectively; P< 0.05 ). CONCLUSIONS: Bupleurum root, scutellaria and baked licorice may have protective effects on the myocardium at different time after medication.