Provided is a method of preparing induced pluripotent stem cells using a synthetic peptide, and more particularly, to a method of preparing induced pluripotent stem cells using a peptide capable of inhibiting the activity of NF-κB and promoting mesenchymal-epithelial transition (MET). Since undifferentiated multipotent stem cells may be efficiently prepared under xenopathogen-free or feeder cell-free conditions without requiring co-culture with animal serum or xenogeneic cells, the method for preparing the induced pluripotent stem cells using the synthetic peptide according to the present disclosure is very useful for developing stem cell therapeutic agents that are clinically applicable.