To design equipment for application in plantation, harvesting, ginning, transportation, storage, oil extraction and processing operations of cotton seeds, the knowledge of various engineering properties for cotton seeds. The study of experiments conducted on cotton seeds at 9.16 % moisture content on dry basis. The results showed that the average value of length, width, thickness, geometrical and arithmetic mean diameters, volume, sphericity, coefficient of contact surface and surface area of cotton seeds were 9.47, 5.57, 4.68, 6.27, 6.58 mm, 129.55 mm3, 66.37 %, 50.32 % and 123.63 mm2, respectively. While; the mean value of bulk and true densities, individual seed mass, one thousand seed, porosity and projected area were 0.457 and 1.051 g/cm3, 0.115 g, 112.22 g, 56.39% and 39.91 mm2, respectively. The study also revealed that the average value of repose angle was 36.22°. While; the lowest value of static friction coefficient for cotton seeds were on stainless steel sheet followed by galvanized iron, plywood and the highest on rubber were 0.320, 0.408, 0.482 and 0.583, respectively. The study also concluded that the mean value of rupture force and deformation ratio of cotton seeds were 76.88 N and 6.11 %. The mean values of terminal velocity and coefficient of drag were 9.34 m/s and 0.55, respectively. Also; the mean value of Reynolds number was 3536 so; the pattern of air flow is in the range of transitional flow.