Method for producing integrated solar cell

A method for producing a thin film solar cell is provided for forming an integrated structure having good power generation efficiency and the thin film solar cell having excellent production efficiency with fewer steps. The method includes a step of forming a first electrode layer on a substrate; a step of forming separation grooves on the first electrode layer with a surface of the substrate exposed at the bottom; a step of sequentially laminating a photoelectric conversion layer and a second electrode layer to form a laminated body S in a way that covers the first electrode layer and the surface of the substrate exposed by the separation grooves; a step of forming opening grooves that are parallel to the separation grooves and deep to a surface position of the first electrode layer; a step of forming the opening grooves in a way to retain a part of the laminated body S at a position separated from two walls; and a step of forming a connection part linking electrically photoelectric conversion elements parti