Abstract: Abstract: The restitution coefficient is an important elementary physical data of the grain related to the research and development of farm machinery. In order to build a collision model between oil rapeseeds and key parts of seeding or harvesting equipment, a restitution coefficient measuring device based on kinematics was designed in this paper, and the restitution coefficient of oil rapeseeds was measured and analyzed by experiment. Research on the collision materials, the thickness of collision materials, the falling height, and the moisture content of oil rapeseed's effect on the restitution coefficient of the 'Huashuang 4' oil rapeseed was conducted by a mixed orthogonal experiment based on the scheme of L8(41×24). Then, single factor tests for factors including the falling height, the material thickness, and the moisture content of oil rapeseeds were carried out and the corresponding regression equations were obtained by analysis. During the experiment, selected rapeseeds were soaked in pure water for about 3 hours and then air-dried in the shade for 2 hours. After that, an 'MB45 Moisture Analyzer' (made by Ohaus) was used to control the moisture content of rapeseeds by drying them in different times, determining it by drying them until the weight did not vary. An existing camera tripod was used to control the falling height and four kinds of materials, including Q235 steel, rubber, aluminum and Plexiglass, in different thicknesses were used as well. For each test, oil rapeseeds were dropped from the same height, rebounded after collision with an inclined plane at a fixed angle, and then received and fixed by two groups of sponge plates covered with lithium grease in different levels. Two groups of different placement data were measured, with which the restitution coefficient can be deduced according to the related formulas. 15 to 25 oil rapeseeds with diameters from 1.80 mm to 1.95mm were selected manually, which should be in good sphericity (if any of which were wizened, not full, or elongated would be ruled out). When the placement data was being determined, the measurement point was required to be the center of a circle which should embrace most of the oil rapeseeds (more than 90%). Experimental results show that the most significant factor is the collision material, followed by the falling height, then the thickness of collision material; the moisture content of oil rapeseeds is the most insignificant factor. Furthermore, the restitution coefficient of oil rapeseeds ascends steadily at first and then more slowly with the increasing of the thickness of collision material, but the restitution coefficient decreases along with the declining of the falling height. Under the condition that the oil rapeseeds' moisture content is 8.06% and the thickness of Q235 steel as the collision material is 1mm, determination coefficient R2 of the regression equation for the curve of the oil rapeseeds' restitution coefficient with the falling height is 0.9979. Under the condition that the oil rapeseeds' moisture content is 8.06%, the falling height is 420mm, and the collision material is Q235 steel, determination coefficient R2 of the regression equation for the curve of the oil rapeseeds' restitution coefficient with the material thickness is 0.9872. Those results above can be an important reference in the designing and developing of high performance rapeseeds seeding or harvesting equipments.