||Perovskite solar cells (PSCs) have a high efficiency, and their price is relatively low; thus, they are attracting considerable attention as a substitute for expensive Si solar cells. However, highly efficient PSCs are not ecofriendly, because they contain heavy metals such as Pb. Therefore, we develop Sn-based PSCs to reduce the Pb content. First, 11 different perovskite precursors are synthesized by increasing the amount of Pb(SCN)2 from 0 to 0.5 M in CH(NH2)2SnI3. Then, PSCs are fabricated, and their characteristics are compared. The Sn-based PSCs with 0.25 M Pb(SCN)2 exhibit a high efficiency of 8.4%, which is significantly higher than that (1.6%) of Sn-based PSCs without Pb(SCN)2. The calculated Pb content of CH3NH3PbI3 is 0.37 g/mL, while that of CH(NH2)2SnI3 containing Pb(SCN)2 is 0.08 g/mL. These results indicate the possibility of producing ecofriendly PSCs.