Abstract: In this study, cockle shell ash was used as a filler material in Stone Mastic Asphalt (SMA) mix to verify the appropriateness and feasibility for the highly traffic roads. SMA is one of the new generations of asphaltic mix and adopted in many countries due to its excellent performance. The main objective of this study is to determine whether the cockle shell as a filler material can improve their performances of Stone Mastic Asphalt on its stability and flow. The manual compaction was carried out to obtain the shell ash and exploited to evaluate the volumetric properties of the design mix. The aggregate gradation of SMA 20 was utilized as the aggregates and 25% increment of cockle shell ash was added as a filler material in this study. The results were compared to conventional or 0% of cockle shell to check the suitability of the materials. The results obtained are adequate and meet the requirement of the standard for SMA Mix.