A solar cell device comprising: a first solar cell array and a second solar cell array disposed side by side in one direction and each including a plurality of solar cell modules disposed side by side along a direction inclined with respect to an installation surface and a holding member holding an outer circumference of each of the solar cell modules; and a support member disposed between the first solar cell array and the installation surface and extending from the first solar cell array to the installation surface, wherein a part of the holding member in the first solar cell array positioned on an upper side in the inclined direction is fixed to a top portion of the support member, wherein a part of the holding member in the second solar cell array positioned on a lower side in the inclined direction is fixed to a side portion of the support member, the second solar cell array is fixed to the side portion of the support member via an attachment member, the attachment member has a first attachment portion attached to the side portion of the support member and a second attachment portion joined with the first attachment portion and supporting the holding member of the second solar cell array from a side of the installation surface side, the support member includes a flange portion protruding from the side portion along a longitudinal direction of the support member, and the flange portion has a notched portion engaging with the first attachment portion, characterized in that the longitudinal direction of the support member is a direction orthogonal or substantially orthogonal to the installation surface. a first solar cell array and a second solar cell array disposed side by side in one direction and each including a plurality of solar cell modules disposed side by side along a direction inclined with respect to an installation surface and a holding member holding an outer circumference of each of the solar cell modules; and a support member disposed between the first solar cell array and the installation surface and extending from the first solar cell array to the installation surface, wherein a part of the holding member in the first solar cell array positioned on an upper side in the inclined direction is fixed to a top portion of the support member, wherein a part of the holding member in the second solar cell array positioned on a lower side in the inclined direction is fixed to a side portion of the support member, the second solar cell array is fixed to the side portion of the support member via an attachment member, the attachment member has a first attachment portion attached to the side portion of the support member and a second attachment portion joined with the first attachment portion and supporting the holding member of the second solar cell array from a side of the installation surface side, the support member includes a flange portion protruding from the side portion along a longitudinal direction of the support member, and the flange portion has a notched portion engaging with the first attachment portion, characterized in that the longitudinal direction of the support member is a direction orthogonal or substantially orthogonal to the installation surface.