A method of preparing super absorbent polymer includes carrying out a crosslinking polymerization of a monomer mixture comprising a water-soluble ethylenically unsaturated monomer having at least partially neutralized acidic groups, a forming agent, a foam-promoting agent and a silicone-based surfactant in the presence of an internal crosslinking agent to form a hydrogel polymer; drying, pulverizing and classifying the hydrogel polymer to form a base polymer powder; and further crosslinking a surface of the base polymer powder in the presence of a surface crosslinking agent to form a surface crosslinked layer. The method produces super absorbent polymer having not only an excellent absorbent capacity and an absorbency under load but also the rewetting phenomenon can be effectively prevented.