Introduction Dapagliflozin, one of the sodium-glucose cotransporter-2 inhibitors, has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and heart failure. In this study, we sought to determine the impact of dapagliflozin on the outcome of radiofrequency catheter ablation (RFCA) for patients with T2DM and atrial fibrillation (AF). Methods This retrospective study included patients who underwent AF ablation between January 2019 to February 2021 at the First Affiliated Hospital of Zhengzhou University. All patients had a history of T2DM and were divided into the dapagliflozin group (n = 79) and the control group (n = 247) according to whether the patients were treated with dapagliflozin after ablation. The definition of AF recurrence was documented atrial arrhythmias over 30 s after a 1-month blanking period. Cox regression models were used to analyze the risk of AF recurrence. Results Overall, 326 patients were analyzed (mean age, 63.7 +/- 10.0 years old; male, 58.9%; paroxysmal AF, 52.8%; recurrence rate, 40.8%). We found that hemoglobin A1c before ablation was higher in the dapagliflozin group than in the control group (7.7 +/- 1.4 vs. 7.3 +/- 1.2, P = 0.007). After a mean follow-up of 15.5 +/- 8.9 months, the dapagliflozin group had a lower recurrence rate than the control group (27.8% vs. 44.9%, P = 0.007). Treatment with dapagliflozin (HR 0.614, +/- 95%CI 0.387-0.974, P = 0.038) was associated with a lower risk of recurrence of atrial arrhythmias (ATa) after ablation in multivariable Cox regression models that adjusted for duration of AF, BMI, AF type, left atrial diameter (LAD), and eGFR. The Cox regression model that incorporated hemoglobin A1c and other antidiabetic agents also demonstrated a similar reduction in the risk of recurrent atrial arrhythmias with dapagliflozin treatment (HR 0.611, +/- 95% CI 0.379-0.985, P = 0.043). Conclusions In patients with T2DM, treatment with dapagliflozin appears to be independently associated with a significant reduction in the risk of recurrent atrial arrhythmias after RFCA.