The invention discloses an acrylate/metakaolin composite grouting material and a preparation method thereof and relates to the field of grouting materials. The preparation method comprises the following steps of: dissolving 5 parts of sodium hydroxide and 27 parts of water glass into 43 parts of water in terms of parts by mass; reducing the temperature of solution to room temperature and then adding 5-20 parts of metakaolin; dispersing a mixture for 10 minutes at high speed and then adding 50 parts of first solution by stirring at low speed and uniformly mixing to obtain a second solution, wherein the first solution is formed by mixing 10-20 parts of acrylate, 1-5 parts of ethylene glycol diacrylate, 1-3 parts of triethanolamine and 0.05-0.1 part of sodium dodecyl benzene sulfonate; mixing 1-2 parts of ammonium persulfate and 81.95-49.9 parts of distilled water to form a third solution; and mixing the second solution with the third solution according to the proportion of 5:1 to obtain the acrylate/metakaolin composite grouting material. The composite grouting material prepared by the preparation method disclosed by the invention is toxic-free and environment-friendly; and in addition, the tensile strength and the durability of a solid sand body can be improved.