A method for manufacturing a high photovoltaic-conversion efficiency solar cell, in which a second conductive type diffusion layer, where second conductive type impurities are diffused, is formed in a first region of a back surface, as a non-light receiving surface, of a first conductive type semiconductor substrate provided with the first region, a second region, and a third region, wherein a first conductive type diffusion layer, where first conductive type impurities are diffused, is formed in the second region, and a high resistive layer, where the first conductive type impurities and the second conductive type impurities are diffused, is formed in the third region between the first region and the second region, the method comprising: a second impurity diffusing step of diffusing the second conductive type impurities on the entire back surface of the semiconductor substrate to form the second conductive type diffusion layer; a protective layer forming step of forming a protective layer on the second conductive type diffusion layer; a first protective layer removing step of removing a portion of the protective layer which covers the second region while tapering a thickness of a portion of the protective layer which covers the third region from an original thickness of the protective layer to almost 0, from a boundary with a portion covering the first region to a boundary with the portion covering the second region; a second conductive type diffusion layer removing step of removing the second conductive type diffusion layer that is exposed after removal of the protective layer, to expose the second region; a first impurity diffusing step of diffusing the first conductive type impurities in the second region and the third region via the portion where the protective layer tapers, to respectively form the first conductive type diffusion layer and the high resistive layer; and a second protective layer removing step of removing the remaining protective layer. a second impurity diffusing step of diffusing the second conductive type impurities on the entire back surface of the semiconductor substrate to form the second conductive type diffusion layer; a protective layer forming step of forming a protective layer on the second conductive type diffusion layer; a first protective layer removing step of removing a portion of the protective layer which covers the second region while tapering a thickness of a portion of the protective layer which covers the third region from an original thickness of the protective layer to almost 0, from a boundary with a portion covering the first region to a boundary with the portion covering the second region; a second conductive type diffusion layer removing step of removing the second conductive type diffusion layer that is exposed after removal of the protective layer, to expose the second region; a first impurity diffusing step of diffusing the first conductive type impurities in the second region and the third region via the portion where the protective layer tapers, to respectively form the first conductive type diffusion layer and the high resistive layer; and a second protective layer removing step of removing the remaining protective layer.