The present disclosure discloses a high-efficiency silicon heterojunction (HJT) solar cell and a manufacturing method thereof, and belongs to the technical field of solar cells. In the solar cell of the present disclosure, an N-type crystal silicon wafer is successively provided with a thin SiO2 layer, a hydrogenated amorphous carbon silicon oxide film layer, a carbon doped SiO2 layer, an amorphous silicon doped N-type layer, a TCO conductive layer, and an electrode on a front surface; and successively provided with a thin SiO2 layer, a hydrogenated amorphous carbon silicon oxide film layer, a carbon doped SiO2 layer, an amorphous silicon doped P-type layer, a TCO conductive layer, and an electrode on a rear surface. The amorphous silicon doped P-type layer includes a lightly boron doped amorphous silicon layer and a heavily boron doped amorphous silicon layer.