This study investigates the enhancement of efficiency in CsSnI₃-based perovskite solar cells (PSCs) through numerical modeling of graphene oxide (GO) as the hole transport layer (HTL) and ZnMgO as the electron transport layer (ETL). The research uses SCAPS-1D simulation software to analyze the performance of the PSC structure ITO/ZnMgO/CsSnI₃/GO/Au. The simulation results show that the optimal thickness of the CsSnI₃ absorber layer is 1.0 μm, with a defect density of 10¹² cm⁻³, leading to a high efficiency of 17.37%. The study also demonstrates that the use of GO as an HTL improves hole collection, while ZnMgO as an ETL enhances electron transport and provides better band alignment with the absorber. The simulation results indicate that the PSC with GO as HTL and ZnMgO as ETL achieves a higher efficiency compared to conventional materials. The study also examines the impact of various parameters such as thickness, acceptor density, and temperature on the performance of the PSC. The results show that increasing the thickness of the CsSnI₃ layer up to 1.0 μm improves the short-circuit current density (Jsc) and open-circuit voltage (Voc), while higher acceptor densities can lead to a decrease in Jsc and Voc. The study concludes that the optimized PSC structure with GO as HTL and ZnMgO as ETL offers a promising approach for developing highly efficient lead-free PSCs.This study investigates the enhancement of efficiency in CsSnI₃-based perovskite solar cells (PSCs) through numerical modeling of graphene oxide (GO) as the hole transport layer (HTL) and ZnMgO as the electron transport layer (ETL). The research uses SCAPS-1D simulation software to analyze the performance of the PSC structure ITO/ZnMgO/CsSnI₃/GO/Au. The simulation results show that the optimal thickness of the CsSnI₃ absorber layer is 1.0 μm, with a defect density of 10¹² cm⁻³, leading to a high efficiency of 17.37%. The study also demonstrates that the use of GO as an HTL improves hole collection, while ZnMgO as an ETL enhances electron transport and provides better band alignment with the absorber. The simulation results indicate that the PSC with GO as HTL and ZnMgO as ETL achieves a higher efficiency compared to conventional materials. The study also examines the impact of various parameters such as thickness, acceptor density, and temperature on the performance of the PSC. The results show that increasing the thickness of the CsSnI₃ layer up to 1.0 μm improves the short-circuit current density (Jsc) and open-circuit voltage (Voc), while higher acceptor densities can lead to a decrease in Jsc and Voc. The study concludes that the optimized PSC structure with GO as HTL and ZnMgO as ETL offers a promising approach for developing highly efficient lead-free PSCs.