Abstract： Objective： To observe the therapeutic effect of Shuxin Tongmai prescription combined with conventional western medicine on the treatment of viral myocarditis and its influence on parameters of cardiac magnetic resonance imaging (CMR). Methods： A total of 108 patients with viral myocarditis were selected and divided into the control group and the observation group according to random number table method，with 54 cases in each group. The control group was treated with conventional western medicine such as antiviral and nourishing myocardium， while the observation group was additionally treated with Shuxin Tongmai prescription based on the treatment of the control group. Both groups were treated for four weeks. The clinical effects in the two groups were compared. The CMR parameters，Chinese medicine syndrome scores，inflammatory mediators including interleukin- 8(IL-8)，interleukin-21(IL-21) and tumor necrosis factor- α(TNF-α)， creatine kinase- MB(CK- MB)，lactate dehydrogenase(LDH)，and levels of myocardial enzymes including cardiac troponin T (cTnT) and cardiac troponin I(cTnI) before and after treatment were observed. The incidence of adverse reactions in both groups was also observed. Results： The total effective rate was 94.44% in the observation group， higher than that of 81.48% in the control group，the difference being significant(P＜0.05). After treatment，the including left ventricular ejection fraction(LVEF) levels in both groups were increased when compared with those before treatment(P＜0.05)，and the levels of left ventricular end- diastolic volume(LVEDV) and left ventricular end systolic volume(LVESV) were decreased(P＜0.05)，and there was no significant difference in the levels of Stroke Volume(SV)，Cardiac Output(CO) and Cardiac Index(CI) between the two groups when compared with those before treatment(P＞0.05). After treatment，the LVEF level in the observation group were higher than that in the control group(P＜0.05)，and the levels of LVEDV and LVESV were lower than those in the control group(P＜0.05)，and there was no significant difference in the levels of SV，CO and CI between the two groups(P＞0.05). After treatment，the levels of IL- 8，IL- 21 and TNF- α in both groups were decreased when compared with those before treatment(P＜0.05)， and the above three levels in the observation group were lower than those in the control group， differences being significant(P＜0.05). After treatment， the levels of CK- MB， LDH， cTnT and cTnI in both groups were decreased when compared with those before treatment(P＜0.05)，and the above four levels in the observation group were lower than those in the control group， differences being significant(P＜0.05). After treatment， the Chinese medicine syndrome scores in both groups were decreased when compared with those before treatment(P＜0.05)， and the Chinese medicine syndrome score in the observation group was lower than that in the control group，differences being significant(P＜ 0.05). No obvious rash， gastrointestinal discomfort， headache and other adverse reactions occurred in both groups during medication. Conclusion：The therapy of Shuxin Tongmai prescription combined with conventional western medicine for viral myocarditis can reduce the degree of cardiac damage，improve cardiac function，reduce inflammatory response and improve clinical effect.