Abstract: It was investigated that 2-mercaptopyrimidine（2-MP）passivated the interface between the perovskite layer and hole transport layer of a triple cation perovskite solar cell,which improved the photoelectric properties of the film and the device. Steadystate and time-resolved photoluminescence fluorescence spectrum characterization results showed that non-radiative recombination of the passivated perovskite film was suppressed. In addition,the work function characterizations by KPFM illustrated that the energy level of PVK/2-MP/Spiro matched better than that of PVK/2-MP/Spiro,that is beneficial to suppress carrier recombination and enhance opencircuit voltage. After passivation,the hydrophobicity of the film was enhanced which is helpful to block water vapor erosion and improve stability. The open-circuit voltage dependence on light intensity shows that 2-MP effectively passivates the interface defects and suppress the non-radiative recombination of carriers. The J-V test showed that the photoelectric performance of the device was significantly improved with passivation,the open-circuit voltage was up to 1.133 V,and the efficiency was up to 21.66%. Moreover,the stability of the optimized device was significantly improved. After 97 days of storage in nitrogen,the efficiency maintained 90% of the initial efficiency.