Objectives: Heart failure (HF) with reduced ejection fraction (HFrEF) is defined as an ejection fraction (EF) of less than40%. An EF of 40% to 50% is known as HF with mid-range EF, which is considered a subgroup of HF with preservedejection fraction, rather than HFrEF. Angiostatin inhibits angiogenesis and the proliferation of mesenchymal stem cells.Though many studies in the literature have focused on the effect of angiostatin on endothelial cell apoptosis, studiesabout angiostatin levels in HF patients are limited. The aim of this study was to evaluate the angiostatin level in systolicHF patients with chronic kidney disease (CKD).Methods: A group of 69 individuals, consisting of patients with a diagnosis of systolic HF with CKD (n=29) and healthy(n=40) subjects, was included in the current study. Serum angiostatin, plasma N-terminal pro-brain type natriureticpeptide, and creatinine levels were assessed, and transthoracic echocardiography was performed.Results: The angiostatin level of the patient group was significantly higher than that of the control group (median:163 ng/mL [25th–75th interquartile range: 48-336 ng/mL] and median: 58.14 ng/mL [25th–75th interquartile range: 18.1-167 ng/mL], respectively; p=0.02). The angiostatin level of HF patients receiving beta blocker therapy was significantlyhigher than that of the HF patients who were not taking a beta blocker (105.3 ng/mL [50.7-220.7 ng/mL] and 70.4 ng/mL [35-224 ng/mL], respectively; p=0.02).Conclusion: To the best of our knowledge, this study is the first to examine this subject. Angiostatin may be an importantmarker in systolic HF patients with CKD. The use of a beta blocker may inhibit angiogenesis and induce apoptosisin HF patients with CKD. Further studies are required.