Selected mechanical properties of pistachio kernel of Ohadi cultivar such as deformation, deformation ratio, rupture force, rupture strength, toughness and hardness were measured as a function of moisture content (at 5 levels of 38.5, 31.0, 24.0, 17.0, and 6.0% wet basis) and compression axis (at three loading positions of x, y, and z). Physical properties of the pistachio kernel such as length, width, thickness, geometric mean diameter, sphericity, surface area were also determined. The results showed that the physical properties decreased linearly by decreasing moisture content. However, all mechanical properties increased with decreasing moisture content, except deformation and deformation ratio which decreased with decreasing moisture content. The highest rupture force, deformation ratio, and toughness in all moisture content levels were obtained for pistachio kernel loaded along the z-axis. While for rupture strength, deformation and hardness, the highest values were determined along the x-axis. The highest force required to initiate kernel rupture was 38.5 N at z-axis for 6% moisture content and the lowest 30.2 N at x-axis for 38.5% moisture content

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