The invention discloses a method for preparing monolayer molybdenum disulfide based on electrolyte solvothermal lithium-intercalation stripping. The method comprises the following steps: taking MoS2 powder as precursor and taking the electrolyte as the solvent in a reaction kettle by using a solvothermal method, intercalating the lithium ion in the electrolyte between MoS2 layers under the production of high purity argon, removing the unreacted MoS2 through a centrifugal process to obtain the monolayer MoS nano-material with intercalated lithium; cleaning for several times by adding acetone tocentrifuge, and finally preparing the high-purity MoS2 nano-material with monolayer structure through the deionized water ultrasonic treatment. The preparation method disclosed by the invention is novel, low in manufacturing cost and simple in preparation process, the lithium ion is sufficiently utilized to intercalate into the MoS2 nano-material, thereby effectively improving the yield of the monolayer molybdenum sulfide.