An extracellular exoinulinase (2,1-β-D fructanfructanohydrolase, EC 3.2.1.7), which catalyzes the hydrolysisof inulin into fructose and glucose, was purified 23.5-foldby ethanol precipitation, followed by Sephadex G-100 gelpermeation from a cell-free extract of Kluyveromyces marxianusYS-1. The partially purified enzyme exhibited considerableit remained stable (100%) for 3 h at the optimum temperatureof 50oC. Mn2+ and Ca2+produced a 2.4-fold and 1.2-foldenhancement in enzyme activity, whereas Hg2+ and Ag2+completely inhibited the inulinase. A preparation of the partiallypurified enzyme efectively hydrolyzed inulin, sucrose, andrafinose, yet no activity was found with starch, lactose, andto hydrolyze pure inulin and raw inulin from Asparagusracemosus for the preparation of a high-fructose syrup. In abatch system, the exoinulinase hydrolyzed 84.8% of the pureinulin and 86.7% of the raw Asparagus racemosus inulin, wherefructose represented 43.6 mg/ml and 41.3 mg/ml, respectively.