Patients with heart failure (HF) often develop hyponatremia owing to the activation of many neurohormonal systems leading to decreased sodium levels. Treatment options for hyponatremia such as water restriction or the use of loop diuretics are present but patients do not always respond to treatment. Ultrafiltration (UF) is used in patients at an advanced stage of congestive HF and unresponsive to medical treatment. Tolvaptan, a vasopressin 2 receptor antagonist, has recently been used in hypervolemic hyponatremia in patients with heart failure. We report a 60-year-old man who had heart failure and hypervolemic hyponatremia that was resistant to medical treatment. Ultrafiltration was started but the treatment was stopped because of catheter infection. Tolvaptan was used for hyponatremia in this case and the patient did not need ultrafiltration again.