Composites have many important properties such as high specific hardness and strength, dimensional stability, adequate electrical properties and excellent corrosion resistance. The composite industry is mostly dominated by thermosetting resins such as epoxy, vinyl ester, unsaturated polyester, phenolic, polyimides. These resins have many advantages such as their relative ease of processing, lower equipment cost for processing and lower material costs. In this study, the effect of chestnut sawdust on the mechanical properties of epoxy matrix composites was investigated. As the resin, thermosetting epoxy resin was preferred as the matrix. As a filler, chestnut wood sawdust, which is produced as a natural waste by local furniture manufacturers, was used. The sawdust was prepared up to 400 micron size and was added to the resin at rates of 5-10-15-20% by weight. Sample preparation was terminated as the resin reached saturation with the addition of 20% sawdust. PTFE material was preferred as the mould because of the very weak adhesion property of epoxy. The prepared mixture was kept in the oven at 180oC for 3 hours to completely harden. Mechanical properties of the samples such as tensile, hardness and impact were investigated. Examination of the broken surfaces was made with SEM images. At the end of the study, it was determined that the addition of 10% by weight chestnut sawdust increased the mechanical properties of epoxy composites. It was also understood from the SEM images that there was a homogeneous mixture in the sample structure.