Tolvaptan has been gradually spread to use as a potent diuretic for congestive heart failure in the limited country. However, the response to this aquaretic drug still is unpredictable. A total of 92 patients urgently hospitalized due to congestive heart failure and treated with tolvaptan in addition to standard treatment was retrospectively analyzed. Responder of tolvaptan treatment was defined as a patient with peak negative fluid balance greater than 500 mL/day, and clinical profiles were compared between 76 responders and 16 non-responders. Responders started to increase daily urine volume (UV) from Day 1 through Day 3. In contrast, non-responders showed no significant increase in daily UV from the baseline up to Day 5. Time between admission and tolvaptan administration was shorter in responders, even without statistical significance (3.3 vs. 4.6 days, p = 0.053). Multivariate analysis revealed that blood urea nitrogen (BUN) [cutoff: 34 mg/dL, odds ratio (OR) 9.0, 95% confidence interval (CI) 1.42-57.3, p < 0.01] and plasma renin activity (PRA) (cutoff: 4.7 ng/mL/h, OR 6.1, 95% CI 1.01-36.4, p < 0.01) at baseline were independent predictors for tolvaptan responsiveness. It suggests that renal perfusion may affect tolvaptan-induced UV. Finally, durations of stay in intensive care unit and total hospitalization were significantly shorter in responders (median: 6.0 vs. 13.0 days, p = 0.022; 15.0 vs. 25.0 days, p = 0.016, respectively). Responders of tolvaptan have lower BUN and renin activity at baseline, and shorten hospitalization period. Trial Registration The study was registered at University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) with the identifier UMIN000023594. https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000024988.