The development of new materials and new manufacturing techniques has accelerated during the last several years. Laser welding is one of these technologies and it has facilitated use of steel sandwich panels. The application of such new structures requires fast optimization procedures to obtain optimal design configuration for a given design case. In order to obtain recommendations concerning the best configuration, different metamodeling methods where used for approximation, optimization and analysis of different core sandwich panels. Application of metamodeling methods for optimization included several steps: 1) design of experiments, 2) numerical experiments based on FE calculations, 3) high precision approximations of experimental data using polynomials, locally weighted polynomials and kriging, 4) multi-objective optimization using three criterions. The results of different metamodeling methods and parameter fitting techniques where compared, with conclusion that kriging gives the best overall approximation results. The metamodel accuracy was increased by introduction of additional parameter inverse proportional to the second moment of area of panel cross section.