We wished to study the protective effects of Wusen Erlian granules, a therapy from traditional Chinese medicine, in experimental viral myocarditis (VMC). Sixty mice were divided into six groups: control group, infection group, ribavirin group, and three Wusen Erlian groups, treated with low, intermediate, or high doses (4, 12, or 20 mg/kg) of Wusen Erlian. Control animals were intraperitoneally injected with culture medium, while animals in other groups received intraperinoneal injections of CoxB3 virus. The Wusen Erlian granules were intragastrically administered on days 0, 1, 2, 3, 4, and 5 after virus inoculation. The experiment was terminated 2 h after the final drug administration. The mice were weighed, and specimens were collected for detection of myocardial enzymes, measurement of organ index, and natural killer (NK) cell activity. The levels of creatine kinase isoenzyme, troponin, and myoglobin were significantly increased in infected animals (all p < 0.05). Compared with infection group, the levels of creatine kinase isoenzyme and troponin were significantly (p < 0.05) decreased in animals that received ribavirin, and in animals that received high or intermediate dose of Wusen Erlian. Furthermore, the spleen and thymus indexes were increased in animals treated with ribavirin, or high/intermediate doses of Wusen Erlian, suggesting immunoregulating functions of these drugs. The NK cell activity was also markedly increased in the above three groups. Wusen Erlian alleviates the CoxB3-induced myocardial injury and exhibits immunoregulating features, leading to protective effects toward myocardial cells in experimental VMC.