The invention discloses a catalyst for ethyne hydrochlorination for synthesis of chloroethylene and a preparation method thereof. The catalyst of the invention is prepared by impregnation of an active carbon carrier, metallic compound active components and a hydroxyl-containing water-soluble carboxylic acid competitive adsorbent. The active components contain at least one component selected from chloride, nitrate, sulfate or phosphate of cobalt, copper, manganese, zinc, bismuth, barium and potassium. The competitive adsorbent contains citric acid, malic acid, salicylic acid, oxalic acid, tartaric acid and lactic acid. The prepared catalyst has characteristics of high activity, good selectivity, simple production method and low cost. By adding the hydroxyl-containing water-soluble carboxylic acid competitive adsorbent, the active components are greatly fixed to the carrier, and high temperature transfer of the active components is reduced; by roasting decomposition of the competitive adsorbent, rich pore structures are generated, and gas dispersion in the reaction process is improved; and dispersity of the active components is improved, catalyst poisoning is alleviated, and life of the catalyst is prolonged.