Roof fixing piece used for rooftop photovoltaic power generating system

The invention discloses a roof fixing piece used for a rooftop photovoltaic power generating system, which comprises a connecting part, a supporting part arranged on the top of the connecting part, and a fixed part positioned at the bottom end of the connecting part, wherein the two sides of the supporting part are symmetrically provided with clamping grooves; the middle part of the supporting part is provided with a screw hole; the fixed part is provided with a through hole; and the roof fixing piece has an integral structure. The roof fixing piece can be directly laid on a roof, and a keel is not needed to be laid on the roof in advance, so that the material and the time are saved, the cost is reduced, a solar cell component is conveniently installed, and the rooftop photovoltaic power generating system is rapidly installed in order.