The invention discloses a solid mercury catalyst for improving activity and stability of acetylene hydrochlorination reaction, which comprises the following components in part by weight: 100 parts of active carbon carrier, 1 to 8 parts of mercuric chloride serving as a main catalysis component and 1 to 10 parts of auxiliary components, wherein the auxiliary components A and B account for 1 to 10 parts respectively, the auxiliary component A is cobalt chloride or manganese chloride, and the auxiliary component B is potassium chloride or ammonium chloride. The solid mercury catalyst aims to solve the problems of over high mercury content of the current mercuric chloride catalyst, poor catalyst stability, over high mercury consumption in the production because the active ingredients are easyto run off, quick catalyst inactivation and serious environmental pollution. The activity and the stability of the solid mercury catalyst are improved by 5 to 50 percent compared with those of the simple mercuric chloride catalyst, the usage efficiency of the catalyst can be effectively improved, the mercury loss is reduced, the production cost is reduced, and the environmental pollution of the mercury is reduced.