In our previous work on the application of DFT method to the study of Cu adsorption on the sphalerite (110) surface, we found that two stable adsorptions of Cu2+ exist on the S sites of sphalerite surface, i.e., Cu adsorption on the top site of S atom and on the bridge site between two S atoms. In present study, the possibility of the migration of Cu from the S-sites to Zn vacancy of sphalerite surface was calculated using transition state (TS) search method. The results of TS search indicated that the Cu adsorbed on the S sites of sphalerite surface can further migrate spontaneously from their adsorption sites to the Zn vacancy and coordinate with the surrounding S atoms. The Cu adsorbed on the bridge site migrates faster than the Cu adsorbed on the top site. The study provides an insight into the mobility of copper during the process of sphalerite activation and helps to in-depth understanding the activation mechanism. (C) 2015 Published by Elsevier B.V.