Some physical properties of grape (Vitis vinifera L.) seeds were determined as a function of seed moisture content varying from 16.55–5.21% (dry basis). The average values of seed length, width, thickness, geometric mean diameter, surface area filling angle of repose and terminal velocity decreased linearly with a decrease in the moisture content from 8.28–7.74 mm, 4.5–4.26 mm, 3.32–3.12 mm, 4.97–4.68 mm, 77.86–68.98 mm2, 27.53–23.78° and 6.8–6.3 m s-1, respectively. The unit mass decreased nonlinearly from 0.056–0.049 g whereas the variation of sphericity was not statistically significant with a decrease in moisture content. The bulk density increased nonlinearly from 577.3– 586.6 kg m-3, while the true density and porosity decreased nonlinearly from 886.2–873.7 kg m-3, and 34.85–32.86%, respectively, when the moisture content decreased from 16.55–5.21%. The static coefficient of friction decreased linearly from 0.38–0.18, 0.37–0.22, 0.5–0.41, 0.38–0.2 and 0.48–0.4 for glass, fiberglass, plywood, galvanized iron sheet and rubber, respectively. The static coefficient of friction of plywood surface was highest at all moisture contents investigated.

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