Abstract: The ITO/ZnO/interface layer (IFL)/MAPbI₃/Sprio-OMeTAD/Au structure of Perovskite Solar Cells (PSCs) and the electron transport layer (ETL)/absorber interface engineering are studied based on the wxAMPS solar cell numerical simulation software micro-platform. The results show that the performance of PSCs is almost unchanged when the defect density of the interface layer is lower than 10¹⁴ cm^-3, and when the defect density is higher than 10¹⁴ cm^-3, the performance of PSCs declines sharply. When the affinity difference(Δχ) between the interface layer and the absorber layer is within the range of -0.7~-0.1 eV, the parameters of PSCs increase with the increase of Δχ; when Δχ is within the range of -0.1~0.5 eV, the solar cell performance shows a gentle increase. When Δχ is greater than 0.5 eV, the short-circuit current (J_SC) of the solar cell shows a gentle increase while the open circuit voltage (V_OC), fill factor (FF) and photovoltaic conversion efficiency (PCE) decrease rapidly. When the band gap E_g increases within 0.9~1.4 eV, the V_OC, FF and PCE of PSCs increase. When the band gap E_g is greater than 1.4 eV, the performance parameters of PSCs remain unchanged basically.