The aim of this study was to clarify the degree of awareness about polycystic kidney disease and its complications among patients that were on maintenance hemodialysis due to polycystic kidney disease and whether the patients notified their relatives about this disease. Seventy hemodialysis patients were enrolled from 20 hospitals/dialysis clinics, which participated in the Lake Biwa Clinical Dialysis Meeting in Shiga. According to the subjects’ medical records, the prevalence of cerebral hemorrhaging, cerebral aneurysms, and valvular heart disease was 11.4%, 17.1%, and 21.4%, respectively. A survey on awareness about polycystic kidney disease showed that 70% of patients recognized at least one complication of polycystic kidney disease (cerebral hemorrhaging: 31.4%, cerebral aneurysm: 41.4%, and valvular heart disease: 8.6%). Although 94% of patients had informed their relatives of their disease, only 57.1% had recommended their relatives visit a hospital/clinic to have a medical check-up for polycystic kidney disease. In addition, only 51.4% knew that a new medicine for this disease, tolvaptan, is commercially available. These results indicate that most patients on hemodialysis due to polycystic kidney disease do not recognize the complications of their condition, which have a marked influence on their prognosis, very well. In addition, about 50% do not strongly encourage their relatives to have medical check-ups for polycystic kidney disease and are not given up-to-date medical information about the disease. To improve the prognosis of hemodialysis patients with polycystic kidney disease and their relatives, we need to give them appropriate information about the disease and access to medical services.