A geothermal power generation system using heat exchange between working gas and molten salt includes a heat collector. A plurality of molten salt containers is disposed in a heat transferor at predetermined intervals from each other. A heat exchanger transfers a heat source of the heat collector to the molten salt in the plurality of molten salt containers. The heat transferor is disposed in the ground. Working gas which receives the heat source of the molten salt via heat exchange enters and exits the heat transferor. A turbine unit is connected to the heat transferor, and generates mechanical energy using energy of the working gas. A power generating unit is connected to the turbine unit, and generates electrical energy using the mechanical energy.