The present invention relates to a synthesis method of silicon carbide whiskers using setae of rice hulls, comprising: the mixing step of preparing material for synthesis by using the setae or mixing the setae and a carbon compound; the first heat treatment step of heating the material for synthesis at 200-1,000 ? for 2-24 hours; the impurities removing step of heating the first heat-treated material at 1,000-1,200 ? for 30 minutes to 3 hours to remove first impurities; the first synthesis step of heating the impurities-removed material at 1,200-1,500 ? for 5 minutes to 3 hours to generate a nucleus of silicon carbide whiskers; and the second synthesis step of heating the material passing through the first synthesis step at 1,550-2,000 ? for 5 minutes to 10 hours to grow the nucleus of silicon carbide whiskers, thereby preparing the silicon carbide whiskers. According to the present invention, whiskers are prepared by using setae instead of conventional rice hulls or carrying out synthesis with the setae and a carbon compound under optimum conditions, thereby improving a production yield of silicon carbide whiskers by three times or more compared with the conventional case, enhancing economical efficiency due to cheap material costs, and improving the quality of the prepared silicon carbide whiskers.
