A solar power system comprising: a low temperature heat collection device which collects sunlight to heat water to thereby generate steam; a high temperature heat collection device which collects sunlight to further heat the steam generated by the low temperature heat collection device to thereby generate superheated steam; a steam-water separation device which is provided between the low temperature heat collection device and the high temperature heat collection device; a steam turbine; a power generator which generates electric power with motive power of the steam turbine; a superheated steam supply line which supplies the steam turbine with the superheated steam generated by the high temperature heat collection device; a water supply line which condenses the steam expelled from the steam turbine into water and supplies the condensed water to the low temperature heat collection device; wherein the solar power system further comprises a low temperature heat storage device which has a first heat storage medium; a high temperature heat storage device which has a second heat storage medium; a sub steam-water separation device which is provided between the low temperature heat storage device and the high temperature heat storage device; a first line (No. 1) which branches from the superheated steam supply line and which supplies the high temperature heat storage device with the superheated steam flowing through the superheated steam supply line; an eighth line (No. 8) which supplies the low temperature heat storage device with the superheated steam which has been supplied from the first line to the high temperature heat storage device; a ninth line (No. 9) which returns, to the water supply line, the steam which has been supplied from the eighth line to the low temperature heat storage device; a second line (No. 2) which branches from the water supply line and which supplies the low temperature heat storage device with the water flowing through the water supply line; a tenth line (No. 10) which supplies steam generated by the low temperature heat storage device to the high temperature heat storage device via the sub steam-water separation device; a third line (No. 3) which supplies the steam turbine with superheated steam generated by the high temperature heat storage device; and a sixth line (No. 6) which supplies the high temperature heat storage device with steam separated by the steam-water separation device; wherein: the low temperature heat storage device stores the heat of the steam which has flowed through the eighth line in the first heat storage medium, and heats the water which has flowed through the second line with the first heat storage medium to thereby generate steam; and the high temperature heat storage device stores the heat of the superheated steam which has flowed through the first line in the second heat storage medium, and heats the steam which has flowed through the sixth line or the steam which has flowed through the tenth line with the second heat storage medium to thereby generate superheated steam. the low temperature heat storage device stores the heat of the steam which has flowed through the eighth line in the first heat storage medium, and heats the water which has flowed through the second line with the first heat storage medium to thereby generate steam; and the high temperature heat storage device stores the heat of the superheated steam which has flowed through the first line in the second heat storage medium, and heats the steam which has flowed through the sixth line or the steam which has flowed through the tenth line with the second heat storage medium to thereby generate superheated steam.