The present invention discloses a preservation device for lead storage battery comprising: a lead storage battery including at least one negative plate, at least one positive plate, at least one separator between said negative and positive plates, an electrolyte holdingly impregnated by said negative & positive plates and said separator and limited in amount such that substantially there is no electrolyte liberated from said negative & positive plates and said separator, and external terminals having one ends respectively connected to said negative and positive plates and the other ends exposed to the outside of the lead storage battery vessel; and an impedance means connected between said external terminals of said lead storage battery during its preservation.Such preservation device permits to prevent a battery preserved in such device from being decreased in capacity without requiring troublesome maintenance such as supplementary charging at regular intervals, even if it is preserved for a long period of time.