Mineralocorticoid receptor antagonists (MRA) improve clinical outcomes in patients with heart failure with reduced ejection fraction (HFrEF) and reduce risk of heart failure (HF) hospitalization in patients with heart failure with preserved ejection fraction (HFpEF). However, the benefit and risks of MRA use are not clear in HF patients and chronic kidney disease (CKD) with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m². We conducted a systematic review evaluating the efficacy and safety of MRA in patients with HF and CKD. PubMed, Embase, and Cochrane Central databases were searched for relevant studies on patients with HF and reduced renal function (defined as eGFR <60 mL/min/1.73 m²). Seven studies with 5,522 patients were included. We found 3 studies in patients with HFrEF, 1 study with HFpEF, and 2 in acute HF and 1 with mixed patient population of HF. Post hoc analyses from randomized controlled trials demonstrated reduction of risk in the primary end point (adverse cardiovascular outcomes and/or all-cause mortality and/or HF hospitalization) with MRA use in the CKD subgroup (eGFR 30 to 60 mL/min/1.73 m²) despite a greater risk of hyperkalemia and higher rates of drug discontinuation. In 3 observational studies, propensity score matching was performed to compare patients treated with and without MRA and did not identify benefits, but conclusions from these studies were limited due to residual confounding and concern for bias. In conclusion, benefits of MRA use in HF appear to be consistent in patients with reduced renal function (eGFR 30 to 60 mL/min/1.73 m).