Abstract: Objective To investigate the efficacy and safety of sacubitril valsartan in heart failure patients with mid-range ejection fraction. Methods A total of 118 cases of heart failure patients with mid-range ejection fraction left ventricular ejection fraction（LVEF） 40%-49% were enrolled in the 900 th Hospital of PLA Joint Logistic Support Force from July 2017 to August 2019. After the stabilization of hemodynamics, patients were randomly divided into experimental group and control group（n=59）. The experimental group and control group was treated with sacubitril valsartan（target dose: 200 mg each time, twice daily） or candesartan（target dose: 16 mg each time, once daily） in addition to the basic treatment. All patients were followed up for 12 months. The primary endpoint, secondary endpoint and safety endpoint were observed. The primary endpoint was the re-hospitalization rate. The secondary endpoint included Minnesota living with heart failure questionnaire（MLHFQ） score, the proportion of patients with New York Heart Association（NYHA） class Ⅱ, all-cause death, LVEF, left ventricular end diastolic diameter（LVEDD）, stroke volume（SV） and N-terminal pro-brain natriuretic peptide（NT-proBNP）. And safety endpoint comprised hyperkalemia, symptomatic hypotension, deterioration of renal function, and angioedema. Results In the control group, 3 patients withdrew from the study and 56 patients average aged（60.4±12.7）years old completed the follow-up, among whom there were 38 males（accounting for 67.9%）. The average age was（60.5±12.6） years and there were 37 males（accounting for 62.7%） in the treated group. Baseline data, including gender and age, showed no statistically significant difference between the two groups（both P＞0.05）. Compared with the control group, the re-hospitalization rate（15.3% vs 33.9%）,median MLHFQ score 31（22-40） vs 47（40-54） were decreased, while the proportion of patients with NYHA class Ⅱ（82.5% vs 64.2%）, LVEF （49.0±6.0）% vs（43.8±7.3）%, SV （91.9±15.8） vs（75.2±13.4） mL were significantly increased in the treated group. There was no significant difference in mortality, LVEDD and level of NT-proBNP and safety endpoint between the two groups（all P＞0.05）. Conclusion Sacubitril valsartan can reduce the risk of rehospitalization and improve the quality of life in heart failure patients with mid-range ejection fraction.