Interface passivation plays a significant role in reducing surface defects in semiconductor materials. In this paper, we present a kind of Al2O3-passivated nickel oxide (NiO) film as hole transport layer for the perovskite solar cells (PSCs). The optimal Al(2)O(3)insulating film between the NiO and perovskite active layers has a capability to decrease the defect states density at the surface of NiO and suppress the carriers recombination at NiO/perovskite interface. The passivation process could apparently improve the efficiencies of corresponding PSCs from 5.64 to 7.12%. Steady-state photoluminescence and transient time-resolved photoluminescence (TRPL) results demonstrate the restraint of charge recombination at the NiO/perovskite interface with passivation. The Hall effect test further shows that the electrical properties of the NiO film can be improved by adjusting the precursor concentration of the Al2O3, which has a certain significance for the application of interface engineering in PSCs. Furthermore, this method has the advantages of simple operation, low cost, and strong reproducibility, which is also good for the working stability of PSCs.