Some physical, mechanical and rheological properties of soybean seed (Glycine max cv. ATAEM-II) were identified at moisture content of 8.02 +/-(0.03), 12.08 +/-(0.12), 16.07 +/-(0.11), 20.11 +/-(0.16) and 24.05 +/-(0.09)% w.b. From initial moisture content with 8.02% to final moisture content with 24.05%, the average length, width, and thickness of seed increased by 11.93, 10.64 and 10.47%, respectively. Arithmetic and geometric mean diameters, surface area, terminal velocity, angle of repose, static friction angles and coefficients on aluminum, stainless steel, galvanized iron, rubber, glass and plywood plates increased with increasing moisture content whereas other all properties such as true and bulk densities, porosity, shpericity, aspect ratio, rupture force, hardness, elastic modulus, Poissons ratio and energy decreased with increasing moisture content. The minimum friction was determined by glass, followed by aluminum, stainless steel, galvanized iron, plywood and rubber plates at all moisture contents. Elastic Modulus ranged between 118.83 and 100.91N mm-2 at initial and final moisture content, respectively. At the initial and final moisture content, the Poisson ratio changed between 0.527 and 0.262, respectively. The best germination ratio with 98.04% was identified at the 20.11% moisture content while the shortest germination duration with 12.96 days was determined at the 8.02% moisture content.