As global energy consumption, climate change, and environmental degradation continue to escalate, the need for sustainable solutions has become more critical than ever. Passive cooling is emerging as a promising approach to improve energy efficiency in the built environment. This research investigates the potential of passive cooling in new buildings, focusing on its ability to lower indoor temperatures and utilize eco-friendly materials. By reviewing the existing literature, case studies, and technological innovations, this study explores the feasibility and effectiveness of passive cooling strategies, providing a basis for future research and practical implementation. Using quantitative methods, the research analyzes temperature variations under different ventilation scenarios to assess the impact of passive cooling. Additionally, it qualitatively examines the thermal properties of various interior finishing materials, including cement, wood, and loess bricks. Software simulations are employed to assess the temperature reduction effects of eco-friendly materials such as wood and clay bricks. The findings indicate that passive cooling effectively reduces indoor temperatures, irrespective of the interior materials used. While materials like wood, known for its thermal efficiency, or cost-effective red clay blocks may influence overall building performance, the core principles of passive cooling remain universally applicable across different material choices.