To provide a solar power system and a solar panel installation method with which, by using a positioning configuration which is not prone to visible vertical misalignment while preserving sunlight lighting efficiency in the positioning of a plurality of solar panels, solar panel installation is easy, and which is suitable to installing a large solar power system on a hill, in wetlands, etc. [Solution] A solar power system comprises a solar panel group (2) in which a plurality of vertically oriented rectangular solar panels (21) are inclined in the same direction, either left or right, at a prescribed angle of inclination (theta), and the lighting faces (22) of each of the solar panels (21) are arrayed in the same plane.