Cathode protection device and storage tank

The embodiment of the utility model provides a cathode protection device and a storage tank. The device comprises a direct-current power supply, a plurality of test reference electrodes and a plurality of alternative cathode cables arranged on the outer surface of a bottom plate of the storage tank, the plurality of alternative cathode cables are used for being electrically connected with the cathode of the direct-current power supply according to a preset test sequence; the plurality of test reference electrodes are arranged in the same plane below the bottom plate of the storage tank and arerespectively used for being connected with a test pile to determine the cathodic protection potential corresponding to the tested test reference electrodes; wherein the cathodic protection potentialis determined by the electromotive force between at least one alternative cathodic cable to be tested and the test reference electrode to be tested, and the cathodic protection potential obtained by the test is used for determ