Objective To explore the effects of Levothyroxine Sodium Tablets combined with Shenmai Injection in the treatment of hypothyroid heart disease.Methods A total of 78 patients with hypothyroid heart disease admitted to our hospital were selected and randomly divided into an observation group and a control group (n =39,respectively).The two groups were treated with Levothyroxine Sodium Tablets and the observation group was additionally treated with Shenmai Injection for two months.The effects,thyroxine level,heart function level and safety between the two groups were compared.Results The overall response rate (ORR) in the observation group was 92.31%,which was much higher than that (74.36%) in the control group (P < 0.05).The post-treatment T3,T4,FT3 and FT4 in the two groups increased greatly,while TSH decreased significantly and the decrease in the observation group was more significant (P < 0.05).The post-treatment LVEF in the two groups increased greatly,and the LVSDD and LVEDD decreased significantly and the decrease in the observation group was more significant (P < 0.05).The incidence (2.56%) of adverse reactions in the observation group was significantly lower than that (17.95%) in the control group (P < 0.05).Conclusion Levothyroxine Sodium Tablets combined with Shenmai Injection have better effects and higher safety in the treatment hypothyroid heart disease than Levothyroxine Sodium Tablets only,and are worthy of popularization.