The aerodynamic properties of seeds and grains are fundamental knowledge for the dimensioning of the machinery used in the processing, storage, harvest and post-harvest operations. The objective of this study was to determinate aerodynamic properties of two quinoa cultivars grains within different moisture contents. The cultivars BRS Piabiru and Real determined their physical properties (dimensions and density), terminal velocity, drag coefficient and Reynolds number, for seven moisture content (12.1, 12.8, 13.9, 15.3, 16.6, 18.0 and 19.5%d.b.). Cultivar Real have greater dimensions and lower densities than BRS Piabiru for the moisture content range studied. From the lowest to highest moisture content, terminal velocity varied from 2.70 to 3.26 m s -1 and from 2.57 to 3.13 m s -1 for cultivars BRS Piabiru and Real, respectively, while drag coefficient varied from 1.91 to 1.42 and from 2.77 to 2.44. Reynolds number is positive related to the moisture content for both cultivars. It is concluded that the moisture content and the physical characteristics of the cultivars have a significant effect on the aerodynamic properties of quinoa grains.