To provide down-sizing of a device and simplification of a manufacturing process by continuously film-forming with an identical mask in formation of total five layers from a lower electrode current collector layer to an upper electrode current collector layer in the manufacturing process of a thin film solid lithium secondary battery.

In the thin film solid secondary battery, the lower electrode current collector layer 3, an active material layer 4 of a lower electrode, a solid electrolyte layer 5, an active material layer 6 of an upper electrode, and the upper electrode current collector layer 7, are continuously film-formed. In this case, mask exchange and atmosphere opening are not required, thereby, downsizing of the manufacturing device and simplification of the manufacturing process are attained. Further, in the film-forming of each layer, oxidation caused by exposure in the atmosphere of the film interface, denaturation due to moisture, and the resultant adverse effect to the battery performance can be eliminated.