In this article, we study the flexoelectricity induced in a prismatic anisotropic bar due to torsion. The simplified strain gradient elasticity theory is considered in this study. The bar is uniform, that is, any cross-section of the bar has a rectangular shape with cubic internal structure symmetry. The traction and higher traction forces effect on the deflection and spontaneous polarization of the bar with different boundary conditions are also discussed. The induced wedge forces are also considered during this study. The magnesium oxide (MgO) physical quantities values are chosen to present a numerical example as one of the practical applications of the problem. The results are discussed and introduced graphically. The most interesting finding in this study is the wedge force directions. When the displacements inside the cross-section of the bar are uniformly distributed, the resultant wedge forces have the same inclination with the cross-section boundary. Meanwhile, if the displacement is not uniformly distributed, the wedge force inclinations with the cross-section boundary are not equal.
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