The invention provides a preparation method for a gold-based catalyst. In the preparation method, a first modification aid is used to modify a carbon material, so that the gold active component preferentially interacts with a sulfonate radical and can stably exist in a form of small clusters, growth of the gold active component particles is effectively inhibited, and thus the high stability of thegold-based catalyst is guaranteed. At the same time, a second modification aid is used to modify the carbon material, so that effects of adsorbing and activating acetylene and dissociating hydrogen chloride are exerted on the surface of the gold-based catalyst. The catalytic energy efficiency is effectively improved when the gold-based catalyst prepared by the method provided by the invention isapplied to synthesis of vinyl chloride through hydrochlorination of acetylene.