The invention relates to a method for preparing a molybdenum disulfide/graphene alternate intercalation structure material. The method includes the following steps that a moderate molybdenum source and a moderate sulfur source are dissolved in water respectively, and are fully stirred to obtain even solutions; a surfactant is added into the sulfur source, then the obtained molybdenum-source solution is slowly dropped into a solution formed by the sulfur source and the surfactant, a uniform solution or colloid is formed, the uniform solution or colloid is heated to 100 DEG C to 300 DEG C at thepressure of 10 MPa to 300 MPa, and is reacted for 3 hours to 48 hours at the constant temperature, and after the reaction is end, a reaction system is naturally cooled to be the indoor temperature, and pressure is released; the obtained powder is washed, dried and calcined, and the molybdenum disulfide/graphene alternate intercalation structure material is obtained. The method is simple in preparing process and environmentally friendly, an intercalation structure of molybdenum disulfide and graphene can be obtained, the interlayer spacing of the molybdenum disulfide is amplified accordingly,and the method has the important application value in the research aspects of a high-efficiency photocatalyst and a new energy material.