It is frequently necessary to admit critically ill elderly patients to intensive care units (ICUs) due to their physiological impairments and co-morbidities. Several life-sustaining therapies such as mechanical ventilation are performed as necessary treatment in these ICUs. Sometimes renal replacement therapy (i.e. dialysis) is considered for elderly patients with complicating serious renal insufficiency. However, although the necessity for dialysis is recognized, some elderly patients may not benefit from this care because of their limited life expectancy. Until recently, life-sustaining support for critically ill elderly patients in Japan has been used routinely, regardless of the medical futility. The issue of providing better end-of-life care for elderly patients even in the ICU is now being raised frequently. We therefore wish to highlight the issue of end-of-life care and decision-making in the ICU, focusing on nondialytic therapy (NDT). The aim of this article was to assess whether NDT is an acceptable optional care for critically ill elderly patients with serious kidney diseases, even in the ICU. We hope our experiences may be helpful to physicians with an interest in decision-making and end-of-life care.