Abstract： Objective To study the clinical efficacy of trimetazidine hydrochloride in the treatment of acute myocarditis. Methods    82 patients with acute myocarditis admitted from July 2018 to June 2019 were selected and divided into observation group and control group according to the random number table method, with 41 cases in each group. The patients in control group were treated with conventional treatment, and the observation group were treated with trimetazidine hydrochloride. The indexes of myocardial enzymes, inflammatory factors, cardiac function, clinical efficacy and incidence of adverse reactions were compared between the two groups. Results The levels of Myo, cTnI, CK-MB in the observation group were significantly lower than those in the control group, the level of hs-CRP, TNF-α and BNP lower than that of the control group. The differences were statistically significant (all P＜0.05); the left ventricular ejection fraction was higher than that of the control group, the left ventricular end diastolic diameter after treatment was lower than that of the control group, the differences between the two groups were statistically significant (all P＜0.05); There was no significant difference in the incidence of adverse reactions between the two groups（P＞0.05）. Conclusion  Trimetazidine hydrochloride in the treatment of acute myocarditis has definite effect, high safety and low incidence of adverse reaction, which is helpful to improve myocardial enzyme spectrum, cardiac function and reduce inflammatory reaction.