CdSe tetrapods (TPs)-modified ZnO served as cathode buffer layer in the inverted polymer solar cell, could not only passivate the surface defects of ZnO, but also fabricate electron percolation pathways and reduce the band offset at the interface between cathode and active layer, which could promote effective carrier transfer and reduce the rate of surface recombination, and thus boost the device efficiency. The improved crystal quality of ZnO and photon absorption are in favor of the increasing of the short-circuit current density (J (sc)). The decreased series resistance (R (s)) and increased shunt resistance (R (sh)) of the entire devices, are beneficial to the fill factor (FF) enhancement. By optimizing the content of CdSe TPs, the power conversion efficiency of the inverted device based on ZnO/CdSe-2 has been greatly improved to 2.91 % with high J (sc) of 8.03 mA/cm(2) and FF of 61.3 %.