Global energy demand is increasing, and the boundaries of fossil fuels are rising due to climate change caused by greenhouse gases. To solve this problem, interest and research on environmentally friendly and renewable energy sources continue to be conducted. Among the many renewable energy sources, solar cells are in the spotlight due to various advantages. Efforts are being made to make low-cost, high-efficiency solar cells using perovskite, which shows considerable efficiency as a solar cell material, but stability problems in various aspects - such as problems that perovskite structures cannot stand well at high temperatures and high humidity, and problems that cannot be fixed to a target phase - has been emerging. This dissertation is intended to provide clues to solving the stability problems of perovskite through modeling and analysis through the first principle calculation of the stability of perovskite solar cells. This study examined the effect of each component on the various stability in perovskite.