The doping density of each layer in a perovskite solar cell (PSC)-hole transport material (HTM), absorber, and electron transport material (ETM)-is a crucial parameter that directly impacts the device's efficiency. Doping density determines charge carrier generation, mobility, and recombination rates, making it essential for optimizing cell performance. In this study, the effect of doping density was systematically investigated through simulations, and the results highlight its significant role in improving the power conversion efficiency (PCE).