The present invention relates to a sealant composition for repairing the punctured hole on a tire, and a preparation method thereof. The sealant composition contains 80-95 wt% of a liquid-state carrier, 0.1-10 wt% of a gel material derived from a water soluble polymer, 1-10 wt% of a latex, 0.1-5 wt% of rigid particles, and 0.1-5 wt% of a surfactant, wherein the sealant can further be added with 0.1-1 wt% of an additive such as a defoamer, a preservative, a corrosion inhibitor, a colorant, a flavoring agent and the like. The present invention further relates to the preparation method of the sealant composition.