The invention discloses a method for synthesizing acrylic acid or methacrylic acid vinsol ester, comprising the following steps: one of vinsols containing hydroxide radical functional groups, acid-binding agent and addition type polymerization inhibitor are dissolved in non-proton transfer solvent, methacrylic chloride or acryloyl chloride is added into the mixed solution, the reaction temperature is 0-85 DEG C, and the reaction time is 0.5-10h; then, the precipitate is filtered, and vacuum extraction is carried out on the obtained filter liquor to remove solvent, so that acrylic acid or methacrylic acid vinsol ester can be obtained; the mass of the non-proton transfer solvent is 100-500% of that of the vinsol; the molal weight of the methacrylic chloride or the acryloyl chloride is 100-500% of that of hydroxide radical of the vinsol containing hydroxide radical functional groups; the dosage of the acid-binding agent is 100-500% of the molal weight of the hydroxide radical of the vinsol containing hydroxide radical functional groups. The synthesized acrylic acid or methacrylic acid vinsol ester can be used for having free radical polymerization reaction, can be applied to the fields such as paint, adhesive, printing ink, paper making, etc. The method has high technical efficiency and good stability of the product.