A floating photovoltaic power station and a load-bearing system thereof are provided according to the present application. The load-bearing system of the floating photovoltaic power station includes an aisle floating body providing buoyancy and forming a first operation and maintenance passage. The aisle floating body is provided with a fixing portion for fixedly connecting with a front side of a photovoltaic assembly, and one photovoltaic assembly is only fixedly connected to one aisle floating body located on the front side of the photovoltaic assembly. In the load-bearing system of the floating photovoltaic power station, the aisle floating body can support the photovoltaic assembly, and can provide buoyancy at the same time.