Invertase was extracted from Korean ginseng(Panax ginseng C. A. Meyer) leaf with deionized water, and then prepared by ammonium sulfate(0.4~0.6 Sat.) fractionation, the enzymological properties of the invertase were investigated, and the results obtained were as follows. The optimum pH and temperature of the enzyme were pH 6.0 and 4$0^{circ}C$ respectively. The enzyme was stable in the pH range of pH 6.0 to 8.0, and at the temperature below 4$0^{circ}C$. The enzyme was inactivated completely by the treatment with some proteases(pepsin, trypsin, papain and ficin) and protein denaturants(8M urea and 6M guanidine-HCI), but not with glycosidases (a-amylase, $eta$-amylase and glucoamylase). The enzyme catalyzed specifically the hydrolization of the $eta$-fructofuranosides such as sucrose and inulin.