The invention provides a composite collecting agent of sulphide ore. The composite collecting agent is prepared from the following raw materials in parts by weight: 15-30 parts of sodium carbonate, 5-8 parts of dianilino dithiophosphoric acid, 10-12 parts of dialkyl phosphorothioate, 15-18 parts of alkyl thio-formate, 5-10 parts of a cosolvent, 15-20 parts of water, 15-18 parts of butyl xanthate, 30-40 parts of kerosene and 8-12 parts of saturate monohydric alcohol. The invention further provides a preparation method of the composite collecting agent of sulphide ore. Compared with the prior art, the composite collecting agent has the following beneficial effects: the recovery rate of associated silver in the ore is effectively increased by 5-10%; the composite collecting agent has the dual functions of a collecting agent and a foaming agent, intensifies recycling, has the advantages of wide source and moderate price, can be directly mixed in the site selection agentia preparation process, is flexible and feasible, and has market promotional value.