The method of linear combination of pseudoatomic orbitals is applied to calculated the surface electronic structure of semiconductors- Besides the form factors of pseudo-potential, the method does not introduce any adjustable parameters. The electronic states and wave functions of the ideal and relaxed (111) surfaces of Si and GaAs arc calculated. The results of Si is compared with Appelbaum and Hamann's results of self-consistent calculation, it is found that both results are consistent well about the position of surface energy levels and distribution of surface electronic charges. It is shown that the surface energy levels shift upward when the Si or Ga atoms at the surface move inward, and shift downwarol when the As atoms at the surface move outward. At the same time the properties of the wave function of surface states often show more obvious changes.