The main goal of this work is to study the relationship between the surface chemistry of activated carbon (AC) and the performance of respective gold-supported catalysts in the acetylene hydrochlorination. For this purpose, a set of modified activated carbons with different levels of oxygenated groups on the surface, but with no major differences in their textural parameters, was prepared. A strong effect of the surface chemistry of activated carbon on the Au/AC catalytic activity was observed. Comparison of characterizations, catalytic results, and DFT calculations suggests that phenol, ether, and carbonyl groups on activated carbon surface are the key members governing the unique catalytic activity and stability of Au3+ catalysts. The comprehensive experimental and theoretical study of the surface chemistry of Au3+ supported on activated carbon support is believed to be of great benefit for the rational design of gold-carbon composite catalysts for acetylene hydrochlorination.