Hyaluronidase is one of the mucopolysaccharide-splitting enzyme and is related to the permeability of the vascular system and inflammation. An anti-hyaluronidase assay guided fractionation of the methanolic extract of Uncariae Ramulus et Uncus has furnished a pentacyclic triterpene, ursolic acid (compound I). Compound I exhibited hyaluronidase inhibitory activity with $IC_{50}$ value of 0.15 mM, and disodium cromoglycate showed the inhibitory activity with $IC_{50}$ value of 1.78 mM as a positive control.