Although tolvaptan, an electrolyte-free water diuretic for congestive heart failure (HF), is reported to have no effect on long-term mortality or HF-related morbidity, there may exist some subgroups of patients who may receive beneficial effect of tolvaptan. The purpose of this study was to identify clinical factors associated with mid-term effect of tolvaptan on clinical outcomes of patients who discharged after acute HF. We retrospectively analyzed 140 patients (88 male; mean age, 77.1 ± 11.0 years) with acute HF who received tolvaptan (initial dose 8.6 ± 3.6 mg/day) during their hospitalization. They were divided into two groups according to how the tolvaptan was used at discharge; 77 in the tolvaptan-continued group and 63 in the discontinued group. The Cox proportional hazards model revealed that eGFR was the only independent predictor for the occurrence of mid-term cardiac events (composite of re-hospitalization due to HF and all-cause death; aHR = 0.9870, p = 0.02597). The Kaplan-Meier survival curves of the two groups demonstrated no difference in cumulative event-free rates. In the subgroup with preserved renal function at admission (eGFR ⩾ 30 ml/min/1.73 m2), the continuous use of tolvaptan increased composite events (aHR = 2.130, p = 0.02549). The continuous use of tolvaptan after discharge did not affect mid-term cardiac events of HF overall but may be associated with increased cardiac events in the subgroup with preserved renal function. These findings suggest that the tolvaptan administration might need to be limited to treatment of in-hospital acute HF.