A method for preparing a dehumidifying element including a superabsorbent polymer (SAP) comprises mixing SAP particles with inorganic salt particles, exposing the SAP particles and the inorganic salt particles to a high humidity atmosphere thereby absorbing the deliquescent inorganic salt by the SAP, and drying moisture inside the SAP that has absorbed the inorganic salt. Accordingly, an amount of the inorganic salt absorbed by the SAP is minutely controlled thus to precisely control a degree of an ion exchange therebetween, thereby freely controlling a hygroscopic property of the dehumidifying element including the SAP. Furthermore, since the SAP particles and the inorganic salt particles are physically mixed together, the mixture ratio therebetween is entirely uniform, and therefore, the reliability of the product can be obtained.