Hhybrid perovskite solar cell, which uses (CH3NH3)PbI3 as a photoactive layer, is receiving extensive attention because of high energy conversion efficiency and simple manufacturing process. However, the inclusion of toxic lead has increased the necessity of developing Pb-free photoactive materials. Thus, we have searched alternative perovskite materials that can replace conventional (CH3NH3)PbI3. Especially, First-Principles-based novel materials design technique is employed to reduce time and cost required for synthesis and characterization of traditional experimental approaches. We have extensively studied on ABX4, A2BX4, A3B2X9 backbone structures to find alternative materials for perovsktie solar cell. Our study has identified a couple of candidate materials which are suitable for photoactive layer based on bandgap and energy level alignment. In addition, analysis on electronic structure has led the understanding of the relationship between constituent elements and bandgap.