In conclusion, we resolved the structures of apo IPO and IPO in complex with Me-Man, Me-Glc and Me-Gal. IPO is proposed to have a tetrameric association by 4 protomers of the b-prism with an additional N terminus, which shows a compact tetrameric association in the JRL family. From gel filtration experiments, we confirmed the tetrameric association of IPO in solution. The N terminus of IPO plays an important role in forming a tetramer. In addition, the binding pocket of IPO was identified and found to bind to Me-Glc, Me-Man, and Me-Gal with similar hydrogen bond networks. Furthermore, the binding constants of IPO were determined by ITC. The IPO structures further extend the diverse quaternary structures of the JRL family of plants and show versatile carbohydrate binding properties regulated by the N terminus. Thus, the wound-inducible protein IPO from sweet potato has versatile carbohydrate binding properties and might play a role in plant defense.