Etidronic acid (HEDP) and Nitrilotri(methylphosphonic acid) (ATMP) were selected as heteroatoms-containing ligands to modify Au catalysts for acetylene hydrochlorination. Results from several analytical methods reveal an optimal mole ratio of Au/ligand (L) of 1 : 1, with obvious increments over the Au 1 -L 1 / AC catalyst. The coordination between the Au and the heteroatoms, especially the collocative presence of N, P, and O promoted electron transfer from the heteroatoms to the Au n + and increased the density of the electron cloud around active centers. This stabilized the Au n + and increased the difficulty in the reduction of Au species, and re-oxidized the Au 0 to active Au n + species. Moreover, the coordination inhibited the migration of active components. The increased density of the electron cloud around active centers also weakens the adsorption capacity for C 2 H 2 and strengthens the adsorption ability for HCl of the catalysts, which is conductive for constructing the micro-environment favorable to the reaction. DFT calculations proved the stabilization effect of the heteroatoms-containing ligands, and the energy sequence of the transition states supported the experimental results.