The invention discloses an aerosol sealing emulsion and a preparation method thereof. The sealing agent is mainly prepared from the following components in parts by mass: 60-90 parts of butadiene monomer, 25-90 parts of styrene monomer 55 parts, 3-15 parts of butyl acrylate, 3-15 parts of lauryl acrylate, 1.5-3 parts of emulsifier, 100-120 parts of deionized water, 0.16-0.35 parts of molecular weight regulator, 0.02-0.04 parts of antioxidant , 5-12 parts of extender oil, 0.1-0.4 parts of initiator, 0.01-0.025 parts of chelating agent, and 0.1-0.5 part of chain terminator. The gas-soluble sealing emulsion of the present invention forms a plug for formation water, and at the same time has good retention and pressure bearing capacity, reduces the water content, improves the extraction efficiency of natural gas, has a good plugging effect on micro-cracks, and prevents cracks Open to ensure the stability of the well wall of the gas well, and can quickly dissolve in shale gas, natural gas, and coalbed methane, and be discharged with the gas and liquid, forming a fast gas path without damage to the underground rock formation.