Abstract: In order to enhance the performance of framed structures, the section and shape of frame structures are optimized at the same time. Using the technique of decomposition two caterogires of variables are separated. The two-level optimization method for the section and shape of framed structures is established. In the sectional level, with the sectional inertia as the design variable, the structural mass is minimized at the constraints of stress and displacement. In the nodal level, with the coordinates of nodes as design variables, the maximal structural displacement is minimized at the constraint of structural mass. The sectional optimization and shape optimization alternately execute until the satisfactory convergence is reached , Consequently the optimal design is obtained for the minimal mass and maximal rigidity. Using MSC/Patran&Nastran software, the two-level optimization prodecure for section and shape of frame structures is implemented. The numerical examples show that the program and algorithm are reliable and feasible.