Shell GTL Saraphalt is a bituminous performance enhancer introduced by Shell MDS (Malaysia) Sdn. Bhd. This product is a versatile additive polymerised from natural gas that undergoes Fischer–Tropsch synthesis. This study evaluates the effect of Shell GTL Saraphalt in bituminous mixture to understand its properties and performance from the binder properties to the compacted samples. The samples were prepared according to Malaysian Public Works Specification for flexible pavement AC14. For this study, the 2% additive was added into the sample using wet method. The base binder used to prepare the samples was 60/70 PEN. Several key tests were conducted to investigate the physical and rheological properties of the bitumen. For the compacted samples, investigation was conducted on their resilient modulus, dynamic creep, moisture susceptibility and rutting. The findings show that by adding 2% Shell GTL Saraphalt into bitumen 60/70 PEN, it generally, reduces the viscosity of the bitumen at temperature ranging 110 ℃ to 130 ℃, thereby improves its workability during mixing and compacting. Further investigation also shows that adding Shell GTL Saraphalt additive enhance the hardness of the bitumen properties and reduce the permanent deformation by approximately 20%. For compacted samples, Shell GTL Saraphalt mixture exhibit stiffer properties, better creep resistance, and higher resistance towards permanent deformation. One clear advantage of using Shell GTL Saraphalt is that the mixture has superior resistance towards moisture damage based on the result of tensile strength ratio and rut depth result. Moisture susceptibility tests are crucial in determine the mixture performance particularly for a tropical climate country like Malaysia which experience heavy rainfall and hot tropical climate. This makes Shell GTL Saraphalt additive a suitable option for Malaysian road conditions.