The application discloses a quadruple-junction cascade solar cell and a manufacturing method thereof. Monolithic integration is performed on a GaInP/GaAs/InGaAs triple-junction solar cell which grows based on an inverse structure and a Ge solar cell so that a quadruple-junction solar cell of which band-gap energy is respectively 1.9/1.4/1.0/0.67eV. A graphene bonding surface with a special structural form is adopted. Electrical loss and optical loss of the bonding interface can be effectively suppressed by excellent conductivity and light transmission of the graphene bonding surface, and releasing of stress is facilitated by scalability of the graphene bonding surface. Therefore, high-voltage and low-current output can be obtained by the prepared quadruple-junction monolithic high-efficiency solar cell so that resistance loss of an ultrahigh-power concentrator solar cell can be effectively reduced and relatively high conversion efficiency can be obtained.