<p>The growing need for lightweight and high-strength materials in automotive industry, especially for rooftop structures, has led to increased focus on fiber-reinforced composites as potential alternatives to conventional metals. This study aims to assess the optimal conditions for enhancing mechanical properties of such composites using RSM approach. Composite materials were prepared using the hand layup technique by incorporating carbon fiber powder filler at varying concentrations of 0%, 2.5%, 7.5%, and 10% into four different fiber matrices namely Kevlar, carbon, glass, and basalt fibers. A total of 20 experiments were systematically designed using RSM to identify the most effective filler proportions. Mechanical properties including Tensile strength, Flexural strength, and Impact strength were evaluated according to ASTM standards. The RSM optimization improved TS by 8.2%, FS by 3.5%, and IS by 2.4%. The RSM analysis effectively determined the filler levels that maximize performance, with the obtained results aligning closely with existing literature. This outcome underscores the applicability of RSM-optimized composite formulations in industrial settings and contributes valuable insights for scalable manufacturing of high-performance composites in automotive rooftop applications.</p>