The　adsorption　of　Cl-2　molecule　on　CuCl(111)　surface　has　been　studied　with　periodic　slab　model　by　Perdew-Burke-Ernzerh　(PBE)　approach　of　the　generalized　gradient　approximation　(GGA)　within　the　framework　of　density　functional　theory　(DFT).　The　adsorption　models　under　different　coverage　of　CuCl　(111)　surface　and　the　adsorption　over　various　adsorption　sites　(top,　hollow,　bridge,　parallel,　and　Cl　site)　have　been　considered.　The　optimized　results　indicate　that　the　adsorption　is　very　stable　when　the　coverage　is　set　to　0.50　monolayer　and　the　most　stable　site　is　parallel.　The　Cl-Cl　stretching　vibrational　frequencies　are　significantly　red-shifted.　The　population　analysis　indicates　that　the　charges　transfer　from　Cu　atoms　to　Cl-2　molecule.　The　favorite　adsorption　occurs　at　the　hollow　site　for　Cl　atoms　adsorption　on　CuCl(111)　surface.