A stacked-layered thin film solar cell has a plurality of independent unit cells comprising a substrate, a first electrode layer, a first photoconductive layer, an interlayer, a second photoconductive layer, and a second electrode layer in a series stacked structure, wherein at least one first separation groove is formed within the first electrode layer and the stacked-layered thin film solar cell is characterized in: at least one second separation groove formed on the interlayer, at least one connection groove passing through the first photoconductive layer and the second photoconductive layer, and at least one third separation groove extending downward at a periphery of each of the unit cells so that the connection grooves and the third separation groove are concurrently located inside a projection zone of the second separation groove.