To investigate the efficacy of Yanhuning injection combined with antiviral therapy in treating acute viral myocarditis (VMC) of pathogenic toxin invading heart syndrome and the influence on serum levels of macrophage migration inhibition factor (MIF) and interleukin (IL)-6. Methods:A total of 300 patients of acute VMC were randomly divided into control group (150 cases) and treatment group (150 cases). The control group was treated with routine therapy and antiviral therapy. Based on control group, the observation group was given with Yanhuning injection, 2 times/d. Courses were for four weeks in both groups. Scores of symptoms and serum levels of cardiac troponin i (cTnI) and Heart-type fatty acid-binding proteins (H-FABP) were compared in 2 groups. Efficacy was analyzed in 2 groups. Serum levels of MIF and IL-6 were measured in both groups. Results:After treatment, symptoms score and serum levels of cTnI and H-FABP were significantly lower than those of observation group (P<0.01). Efficacy rate of observation group was 88.59％, which was remarkably higher than control group 81.08％ (P<0.05). Serum levels of MIF and IL-6 of observation group were evidently lower than those of control group (P<0.01). Conclusion:Efficacy of Yanhuning injection combined with antiviral therapy in treating acute VMC of pathogenic toxin invading heart syndrome, which is related to down-regualtion of serum levels of MIF and IL-6.