Abstract: Carbonized coconut fiber of approximate particle sizes 100 and 50 μm were characterized in terms of pH, loss on ignition, surface area, aggregate structure and moisture content, used as filler in compounding natural rubber (NSR10) and vulcanized using efficient vulcanization system and compared with a commercial filler (N330). The cure characteristics of the various mix were determined at 185°C using Monsanto rheometer model ODR2000. The Mooney viscosity was carried out using MK111 Mooney viscometer. Tensile strength, modulus, elongation at break, compression, hardness and abrasion resistance were measured as a function of filler volume fraction loading. It was found that vulcanizates with 0.36 filler volume fraction showed optimum tensile strength of 38 mpa for carbon black and 0.43 filler volume fraction of 10 mpa for carbonized coconut fiber. Hardness property increased with increased filler loading for both fillers and carbon black filled vulcanizates showing superior hardness.