Compact blocking layers made of wide band gap semiconductors, such as TiO2 , ZnO, are widely used to suppress recombination at the conductive FTO substrate/electrolyte interface in dye or quantum dot sensitized solar cells, especially in the solid-state devices. Though sharing similar mechanism, blocking layers in p-type sensitized solar cells are rarely studied. Our recent works have demonstrated that the compact NiO films dependent upon the preparation ways play important roles in both p-type dye and quantum dots sensitized solar cells. In p-type dye sensitized NiO solar cell, the compact NiO layer prepared by spin-coating of a sol-gel film, can prevent the recombination at the FTO glass/electrolyte interface and retard the whole cell’s recombination kinetics. Therefore, the fill factor and photovoltage can be increased, leading to a 40.77% improved performance of p-type solar cell. In p-type organometal halide perovskite sensitized mesoporous NiO solar cell, it is found that only the spray pyrolysis deposited NiO dense film is effective for selective hole gathering, rather not the sol-gel deposited NiO dense film. The difference may be ascribed to their coverage status on the rough FTO glasses. The existence of such a NiO block layer not only effects on the cell performance but also determines the current flow direction in the p-type perovskite sensitized NiO solar cell.