BACKGROUND Patients with chronic heart failure (CHF) frequently develop hyperuricemia, an elevated serum uric acid level, associated with adverse outcomes. Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, demonstrates reduction in cardiovascular mortality and hospitalization in patients with CHF and ejection fraction (HFrEF), irrespective of diabetes. However, dapagliflozin’s effect on the uric acid levels in patients with CHF and hyperuricemia remain unclear. AIM To investigate the effects of dapagliflozin on uric acid levels in CHF patients with hyperuricemia. METHODS We conducted a randomized, double-blind, placebo-controlled trial in 200 patients with CHF and hyperuricemia, with HFrEF and serum uric acid levels ≥ 7 mg/dL (≥ 416 μmol/L). The participants were randomly assigned to receive a daily dose of 10 mg dapagliflozin or placebo for 24 months. The primary endpoint was the change in serum uric acid level from baseline to 24 months. Secondary endpoints included changes in left ventricular ejection fraction (LVEF), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and quality of life (QoL) scores, as well as the incidence of cardiovascular death and hospitalization for heart failure. RESULTS At 24 months, dapagliflozin significantly reduced serum uric acid levels by 1.2 mg/dL (71 μmol/L) compared with placebo (95%CI: -1.5 to -0.9; P < 0.001). Dapagliflozin also significantly improved LVEF by 3.5% (95%CI: 2.1-4.9; P < 0.001), NT-proBNP by 25% (95%CI: 18-32; P < 0.001), and QoL scores by 10 points (95%CI: 7-13; P < 0.001) and reduced the risk of cardiovascular death and hospitalization for heart failure by 35% (95%CI: 15–50; P = 0.002) compared with the placebo. Adverse events were similar between the two groups, except for a higher rate of genital infections in the dapagliflozin group (10% vs 2%, P = 0.01). CONCLUSION Dapagliflozin significantly lowered serum uric acid levels and improved the clinical outcomes in patients with CHF and hyperuricemia. Therefore, dapagliflozin may be a useful therapeutic option for this high-risk population.