This research includes testing several different materials for each layer of the five-layer perovskite solar cell (CH 3 NH 3 PbI 3 ) and choosing the best material for each layer of the cell in order to obtain the highest efficiency of the perovskite solar cell, as well as studying the effect of both the thickness of the absorption layer and the back surface field layer on the performance of the solar cell using the computer simulation program (SCAPS1-D), where the perovskite material (CH 3 NH 3 PbI 3 ) was adopted as an absorption layer in the solar cell with a thickness of (1 µm), and titanium dioxide (TiO 2 ) was selected from among several different materials as a window layer with a thickness of (0.05 µm), Fluorine-doped tin oxide (FTO) was selected from among a number of different materials as a transparent conductive oxide layer with a thickness of (0.1 µm), as well as a buffer layer of zinc oxide (ZnO) with a thickness of (0.05µm) and after studying each cell layer and selecting the best one for each layer the structure of the four-layer solar cell became as follows:(CH 3 NH 3 PbI 3 /TiO 2 /ZnO/FTO). The outputs of the solar cell were as follows: [Voc=1.263(V), Jsc=24.01 mA/cm2, FF=89.017%, ƞ=26.94%]. Finally, the back surface field layer was selected, which is zinc telluride (ZnTe) with a thickness of (0.05 mµ). The structure of the five-layer solar cell became as follows: (ZnTe /CH 3 NH 3 PbI 3 /TiO 2 /ZnO/FTO)). The final output of the perovskite solar cell (CH 3 NH 3 PbI 3 ) was as follows: [Voc=1.288(V), Jsc=25.04mA/cm2, FF=89.54%, ƞ=28.88%].