Inclusion Criteria:  Male or female subjects aged ≥ 18 years and ≤75 years  Diagnosed as chronic heart failure with preserved ejection fraction according to the Guidelines for Diagnosis and Treatment of Heart Failure in China 2018  Have symptoms and/or signs of chronic heart failure at least 30 days before the trial LVEF≥50% according to echocardiography during screening stage BNP > 130 ng/L and/or NT-proBNP > 400 ng/L  Cardiac structural changes according to echocardiography during screening stage, in line with at least one of the following:  : LAVI>34ml/m2 : E/e'≥13, average e'(interventricular septum and free wall)<9cm/s NYHAⅡ-Ⅲ Patients with hypertension received a stable dose of antihypertensive therapy for at least 4 weeks and kept their blood pressure at an ideal level for at least 2 months Ability to understand the requirements of the study and willingness to provide written informed consent Have no pregnancy program and take effective contraceptive measures voluntarily Abide by the experimental protocol and cooperate with the data collection according to the researcher's judgment  Exclusion Criteria:  People with any of the following cardiovascular diseases:  Patients with acute decompensated heart failure who need to use quick-acting diuretics, vasodilators, or positive inotropic drugs for treatment, or in the adjustment period of acute decompensated heart failure treatment, and the adjustment time is less than 1 month Clinical evidence of acute coronary syndrome (including myocardial infarction, unstable angina pectoris), or prior revascularization (such as PCI, CABG), or implantable device (such as ICD, CRT), or other cardiac/cardiovascular procedures within 6 months before screening stage Implantable devices (e.g. ICD, CRT), revascularization (e.g. PCI, CABG), or other cardiac/cardiovascular procedures are expected to be performed during the trial period Patients with acute myocarditis, invasive cardiomyopathy, constrictive pericarditis, cardiac tamponade, hypertrophic obstructive cardiomyopathy, cardiac shock, hemodynamic abnormalities of heart valve disease significantly narrow and/or regurgitation (moderate or above, etc.), Ⅱ degrees above Ⅱ type atrioventricular block placement pacemaker therapy, average QTc > 450 ms or heart rate < 50 times/min Patients with pulmonary artery embolism caused by pulmonary hypertension, chronic obstructive pulmonary disease and other serious pulmonary diseases Hypertension that is difficult to control with medication (systolic blood pressure ≥180 mmHg and/or diastolic blood pressure ≥110 mmHg) Symptomatic hypotension and/or systolic blood pressure <100 mmHg Severe renal insufficiency: eGFR < 30 ml/min/1.73m2 ALT and AST > 3 times upper the limit of normal values in local laboratories, and/or total bilirubin > 1.5 times upper the limit of normal values in local laboratories Serum potassium ≥5.5 mmol/L HbA1c≥9.0%, or fasting blood glucose >13.9 mmol/L Diabetic patients who are using sodium-glucose cotransporter 2 inhibitors and cannot stop using them during the trial, such as dagliredin, entagliredin, and cagliredin The ECG examination indicated the onset of atrial fibrillation during the screening period or previous history of atrial fibrillation Hemoglobin < 9.0 g/dL Patients have stroke 3 months before the screening period Concomitant mental illness and poor condition control, which affects the signing of informed consent or presentation of adverse events Patients with active malignancies (including those currently under oncology treatment) Unable to conduct the 6-minute walking distance test due to physical impairment or other non-cardiac reasons Women who are pregnant or lactating Allergic constitution, or allergic to the test drug or its ingredients Participate in clinical trials of other drugs within 3 months before screening The researchers did not consider it appropriate to participate in this study