Natural rubber was reinforced with cashew nut shell powder (CNSP) at 0, 10, 30 & 50g respectively, with particle size of 450µm. the cured samples were evaluated for tensile strength, hardness, and abrasion resistance, also evaluated were pH and moisture content. The pH result revealed cashew nut shell powder as an acidic filler with pH of 4,97 and moisture content of 0.72%. There was increase in hardness as the filler loading were increase for 0-50g. Similar result was obtained in the abrasion resistance, as the filler loading were increase the percentage abrasion was reduced, but it was no so for the tensile strength, the sample filled with 50g of CNSP revealed the best tensile strength while that filled with 30g CNSP revealed the poorest compared with the control sample.