Abstracts The diffusion and adsorption behaviors of the Si adatom on the defect-induced H-terminated Si(0 0 1) surfaces are investigated by empirical tight-binding (ETB) method in this paper. The surface adsorption energies are specially mapped out, from which the favorite binding sites and several possible diffusion pathways are achieved. It is observed from this research that the diffusion energy barriers of the Si adatom near the defect on the hydrogenated Si(0 0 1) surface are higher than those on the non-hydrogenated surface. With the shortening of the structural period, it takes more energy for the Si adatom to escape from the single dimer vacancy (SDV). From this paper, we can find that SDV is a good adsorption point.