Research on natural fibres has been carried out from past decades as a result of developing low cost, eco-friendly materials. The objective of this study is to fabricate composites utilising sawdust of various proportion and compare the mechanical properties like tensile, flexural and hardness within dry condition and with respect to specimens immersed in distilled and salt water. The composites with constant reinforcement 15%, different percentage of matrix (85, 80, 75, 70%) and filler (0, 5, 10, 15%), respectively by mass, are developed by hand layup method and is compared for their mechanical properties. Mechanical properties of composite fabricated from sawdust up to certain percentage showed an improvement when compared to composite with no filler; with further increase in filler, a drop in mechanical performance is noticed. An increase in tensile strength by 12.75%, flexural strength by 5.94%, hardness by 18.34%, tensile modulus by 100.3%, flexural modulus by 60.4% is observed in dry condition compared to the composite with no filler. Mechanical degradation in tensile strength, tensile modulus, hardness, flexural strength for the samples subjected to ageing in sea and distilled water is observed. Flexural modulus after ageing increased with filler addition up to a certain percentage and with further increase in filler, a decrease is noticed. Higher mechanical degradation (except flexural modulus) is observed for those specimens immersed in sea water.