The invention relates to a fog seal material and a preparation method thereof. The fog seal material comprises, by mass, 10 to 30 parts of ultrafine cement, 100 parts of emulsified bitumen, 10 to 20 parts of a regeneration agent, 5 to 15 parts of an osmotic agent, 3 to 7 parts of a retarder, 3 to 5 parts of an early strength agent, 1 to 3 parts of a water reducing agent, 2 to 6 parts of a coupling agent, 20 to 60 parts of fine sand and 4 to 18 parts of water. The ultrafine cement in the invention undergoes a hydration reaction with water and moisture in the emulsified bitumen so as to produce a hydration product with cementing effect, and the hydration product firmly bonds fine sand with aggregate exposed after shedding of asphalt on an old pavement through a chemical mode; demulsification of the emulsified bitumen is promoted at the same time, and demulsified bitumen particles form a film and are interwinded with the hydration product to form an interpenetrating polymer network structure, thereby exerting consolidating effect on the bitumen; moreover, the hydration product is alkalescent and can improve physical adhesion between the bitumen and the exposed aggregate; thus, through the above-mentioned physical and chemical bonding effects, adhesion between the fog seal material and the old pavement is improved.