The world population has indeed been experiencing rapid growth. Along with the population, waste accumulation is also rising exponentially. Utilizing waste materials in construction engineering projects is a desirable and promising trend. Several studies showed that human hair fibers can improve the tensile strength and fatigue resistance of asphalt mixes, while fly ash can improve their durability and stiffness. This study aims to modify asphalt mix by incorporating human hair fibers and fly ash to reduce waste accumulation and improve the performance of flexible pavements. 15 blocks of modified asphalt mix were prepared and it was evaluated and compared with the normal mix. The modified asphalt mix was tested using the Marshall stability test on 15 blocks, with human hair fiber added in percentages equivalent to 3% to 7% of the bitumen content, increasing by 1% increments, and fly ash added at 4% to 8%, increasing by 2% increments. The results showed that incorporating 6% fly ash and 4% hair fiber (by weight of bitumen) into the asphalt mixtures not only increases stability but also reduces bitumen content by 3%. These findings offer a promising avenue for developing sustainable asphalt mixes, which can contribute significantly to addressing challenges related to waste accumulation and resource depletion on a global scale. By leveraging waste materials like fly ash and hair fiber in asphalt production, we can potentially mitigate environmental impacts while improving the performance and longevity of road surfaces.