Research of lead-free perovskite based solar cells has gained speedy and growing attention with urgent intent to eliminate toxic lead in perovskite materials. The main purpose of this work is to supplement the research progress with comparative analysis of different lead-free perovskite based solar cells by numerical simulation method using solar cell capacitance simulator (SCAPS-1D) software. In this work, the device simulation is carried out in the n-i-p configuration of FTO/[6,6]-Phenyl-C61-butyric acidmethyl ester (PCBM) /Perovskite layer/ Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine(PTAA)/Au using six different lead-free perovskite materials. The impact of different perovskite materials layers including hole and electron transport layer thickness, doping concentration on solar cell performances has thoroughly been investigated and optimized. CsSnI3 based perovskite solar cell shows the highest power conversion efficiency of 28.97 % among all the lead-free perovskite based devices. This clearly indicates that it’s possible to achieve high-performance lead-free perovskite solar cells experimentally at par with lead based perovskite solar cells in future research.