The mechanical and aero-dynamic properties such as coefficient of friction, hardness, repose angle, terminal velocity, Reynold's number and drag coefficient for faba bean and lentil seeds were determined at different levels of seed moisture contents while shear force and shear stress of faba bean seeds on both lateral and longitudinal direction were also determined at different levels of seed moisture contents. The obtained results showed that, coefficient of friction changed with type of friction surface and seed moisture contents where it was increased with the increasing of seed moisture contents. Meanwhile for faba bean and lentil seeds, stainless steel surface recorded the lowest values of friction coefficient whereas the rubber surface recorded the highest values. As well, the repose angle increased with the increasing of seed moisture contents. However, hardness, shear force, shear stress decreased with the increasing of seed moisture contents. For aero-dynamic properties both of terminal velocity and Reynold's number of studied crops increased linearly with the increasing of seed moisture contents. While, drag coefficient decreased by increasing the terminal velocity. Mathematical relationships were developed for the studied crops to relate the obtained values of all mechanical and aero-dynamic properties with the changes in seed moisture contents.