Abstract: The present invention relates to a method for manufacturing a novel bactericide consisting of an electrolytically treated liquid having high bactericidal action prepared from raw water by using electrolysis, wherein less electric power and water are required, the structure of the apparatus used therefore is a small scale, simple, and can be operated for long periods of time, and can reduce the manufacturing costs. The invention further relates to the apparatus for manufacturing the same, the bactericide that is manufactured by such a method, and a sterilizing method.