The invention provides a high-power low-voltage silicon-based thin film solar cell and a manufacturing method thereof. The method comprises the following steps of: etching a front electrode layer P1 by laser; etching a silicon-based thin film layer P2 by laser; and etching a back electrode layer P3 by laser. The method is characterized in that a first channel, a second channel and a third channelare respectively formed on the front electrode layer P1, the silicon-based thin film layer P2 and the back electrode layer P3 etched by laser; the front electrode layer, the silicon-based thin film layer and the back electrode layer have a plurality of sub cell areas; and a common area electrode is arranged between adjacent sub cell areas. The method disclosed by the invention can be used for manufacturing high-power low-voltage solar cells.