Driven by global carbon neutrality goals, bamboo fiber-reinforced PP composites have shown significant potential for automotive applications due to their renewability, low carbon emissions, and superior mechanical properties. However, the environmental complexities associated with compression molding process parameters, which impact material properties and carbon emissions, pose challenges for large-scale adoption. This study systematically optimized the compression molding process of bamboo fiber-reinforced PP composites through a three-factor, five-level experimental design, focusing on preheating temperature, preheating time, and holding time. Additionally, an innovative life cycle assessment (LCA) was conducted to evaluate the environmental impact. The results indicated that at a preheating temperature of 220 °C, preheating time of 210–240 s, and holding time of 40–50 s, the material achieved a tensile strength of 35 MPa and a flexural strength of 45 MPa, with a 15% reduction in water absorption. The LCA further highlighted energy consumption, the compression molding process, and material composition as the primary contributors to carbon emissions and environmental impacts, identifying key areas for future optimization. This study provides an optimized framework for compression molding bamboo fiber-reinforced PP composites and establishes a theoretical foundation for their low-carbon application in the automotive industry. Future work will explore the optimization of bamboo fiber content and process parameters to further enhance material performance and reduce environmental impact.