An analysis is presented of the stress field of a dislocation over the central plane of an infinite anisotropic plate with the dislocation lying in the plane. Basic expressions for such a field are given. The stress decreases monotonically as the thickness of the plate decreases. Thus, as expected, the internal stress field in the plate is weaker than in the bulk material for both isotropic and anisotropic cases. Anisotropy may either enhance or reduce the effect of thinning on the relative strength of the stress field (&sgr;/&sgr;inf., where &sgr;inf.is the stress in the infinite medium) when compared to the isotropic case. Criteria for differentiating the two opposite effects are presented.