Abstract: In this paper, the expansions of displacements and stresses of a plate with an edge crack are derived, according to the theary of anisotropic elasticity and the boundary conditions on tha crack surfacesa on the basis of above analysis, the stress intensity factors of orthotropic plates with central cracks, double edge cracks and nesa-hole cracks are calculated by means of generalized variational method.The convargencis of the computational resuits are satisfactorily well for all of the cases mentioned above.Finally, the reaults for isotropic cases agree with those of Ref (8) nicely.