The present invention relates to a
super absorbent polymer and a preparation method thereof. The
super absorbent polymer includes surface crosslinked
polymer particles prepared by surface crosslinking of particles of a base resin, wherein the base resin is polymerized from a
monomer composition including water-soluble
ethylene-based unsaturated monomers, and a water-soluble component, wherein the water-soluble component has a ratio (dwt / d(log M)) of 0.9 or less over molecular weights (M)
ranging from 100,000 to 300,000 when measured from an eluted solution after swelling the
super absorbent polymer for 1 hour, and wherein the content of the water-soluble component is 5% by weight or less, based on the total weight of the super absorbent polymer, when measured after swelling the super absorbent polymer for 1 hour. The super absorbent polymer has excellent liquid permeability even when swollen without a reduction in
centrifuge retention capacity or absorbency under load while having improved permeability.