Disclosed are a cleaning and disinfecting method for treating the surfaces of hemodialysis equipment which are exposed to a dialysate or pure water which comprises the use of electrolyzed hyperacidity water for cleaning and disinfection, as well as a cleaning disinfectant consisting of electrolyzed hyperacidity water, and a cleaning and disinfecting apparatus. The method insures effective cleaning and disinfection and even elimination or inactivation of endotoxins in a reduced time, efficiently, and with reduced water consumption.