Abstract: Based on one-dimensional B₃ spline interpolation-semidiscrehzation, unified calculating formulae have been developed for displacements and forces of orthotropic thin plates and shallow shells, The written code is suitable for orthotropic haperboloidal shells, cylindrical shells and thin plates with simple supports on two opposite edges, and various support conditionson the other two, It can deal with concentrating, distributed loads, linearly valing distributed loads and the conbinations of them, The results of four examples show that the proposed approach is efficient in the analysis of thin plates and shallow shells.