ABSTRACT Type 2 diabetes mellitus (T2DM) and heart failure (HF) are common in clinic, and they often coexist, triggering poor prognosis of patients and increasing hospitalization rates and mortality. Due to some common pathophysiological mechanisms between T2DM and HF, the two have synergistic effects and require collaborative management . In terms of the treatment of T2DM combined with HF, the effects of drugs on both diseases need to be considered to prevent the impact of HF drugs on glycometabolism. As an SGLT2 inhibitor, dapagliflozin can excrete glucose through the kidneys, reduce blood volume, decrease cardiac load to some extent, improve HF symptoms, and better control blood glucose . Therefore, this study selected 60 HF patients complicated with T2DM as the research subjects, and divided them into control group (CLG, conventional medical treatment) and observation group (ONG, dapagliflozin treatment) to explore the effects of dapagliflozin through comparative analysis. According to the results, compared with CLG, ONG had better improvement of blood glucose, cardiac function, and serum levels (P < 0.05), and a lower rehospitalization rate (P < 0.05), with no obvious between-group differences in the incidence of hypotension and emaciation (P > 0.05). These results showed that dapagliflozin in the treatment of T2DM with HF can improve blood glucose levels, cardiac function indexes and inflammatory factor levels, and decrease rehospitalization rates, presenting good clinical efficacy.