This paper examines the combined effect of perovskite/silicon (Si) material on the performance of a surface plasmon resonance (SPR) sensor using the Kretschmann structure. The proposed sensor incorporates the BAF10/Cu/perovskite materials/Si/sensing medium (SM) layers. This paper incorporates the optimized parameters into the proposed sensor by comparing the results without perovskite material and existing work. The proposed modified Kretschmann structure consists of perovskite material such as CsPbI3, FASnI3, KSnI3, and CsSnI₃, with few Si layers. All the performance parameters are calculated at 633 nm wavelength. The sensitivity (S), full width at half maximum (FWHM), detection accuracy (DA), and figure of merit (FoM) of 348.75°/RIU, 3.22°, 0.31/° and 108.11/RIU using perovskite material of KSnI₃, are measured, respectively by the proposed sensor. The perovskite material of KSnI₃ shows the best performance parameter among CsPbF₃, FASnF₃, and CSSnF₃. These results should greatly impact the biosensing application, especially for chemical and biochemical.