The present study was undertaken to investigate the effect of moisture content on engineering properties of OL-09 variety of oat grains. Different engineering properties such as length, width, thickness, geometric mean diameter, volume, surface area, sphericity, bulk density, true density, porosity, angle of repose and angle of internal and external friction were determined in a moisture range of 8%-14% (wet basis, w.b) using standard methods. The physical properties such as length, width, thickness, geometric mean diameter, volume, surface area and sphericity significantly (P <0.05) increased from 15.01 to 16.19 mm, 3.06 to 3.60 mm, 2.78 to 3.11 mm, 5.03 to 5.65 mm, 37.00 to 52.98 mm3, 76.03 to 94.80 mm2 and 33.58% to 35.01%, respectively as the moisture content increased from 8% to 14%.In the same moisture range, bulk density decreased from 474.32 to 408.19 kg/m3, while true density, porosity and thousand grain weight increased from 1017.54 to 1132.90 kg/m3, 53.35% to 63.94% and 41.45 to 44.84 g, respectively. Frictional properties like angle of repose, coefficient of internal friction and coefficient of external friction for wooden surface and galvanized iron sheet increased from 21.26 to 25.46˚, 0.67 to 0.76, 0.55 to 0.70 and 0.49 to 0.63 with increase in moisture content in same range, respectively. The coefficient of determination, obtained R2 for the considered various engineering properties showed a close correlation with increase in moisture content.