b-D-fructofuranosidase (EC 3.2.1.26), also termed invertase, has biotechnological potential for use in food industry, especially in confectionery industry, producing invert sugar (1:1 mixture of D-glucose and D-fructose) from hydrolyzed sucrose. In this work we are showing the production and characterization of extracellular β-D-fructofuranosidase produced by the filamentous fungus Aspergillus ochraceus. A. ochraceus was isolated from soil and identified by André Tosello Foundation, Campinas – SP. Higher levels of extracellular b-D-fructofuranosidase were obtained when the fungus was grown for 96 hours in Khanna medium supplemented with sucrose 1%, under orbital agitation (100 rpm). The extracellular enzyme was purified 187-fold (31% recovery) in two steps using DEAE-Cellulose chromatography and Sephacryl S-200 gel filtration. The invertase activity was measured by the release of reducing sugars from sucrose, using the method of Miller (1956). Extracellular b-D-fructofuranosidase is a homodimeric glycoprotein with 44% of carbohydrate content and molecular mass of 135 kDa (Sephacryl S-200) and 81 kDa (SDS-PAGE). The optima of temperature and pH were, respectively, 60ºC and 4.5. The purified enzyme was stable up to 1 hour at 60ºC in aqueous solution. The enzyme exhibited Km and Vmax for sucrose and raffinose of 13.4 mM, 7.37 mM, 42.13 U/mg protein and 22.39 U/mg protein, respectively. The enzyme was specific for sucrose and raffinose. The enzyme activity was enhanced by Mn²⁺ (57%), Mg²⁺ (50%), Na⁺ (35%) and Ba²⁺ (20%), and inhibited by Cu²⁺ and Hg²⁺. Transglycosylation reactions were not detected, since only glucose and fructose were detected as products from sucrose hydrolysis, using TLC. In summary, the thermostable extracellular β-D-fructofuranosidase described may have biotechnological potential. Financial Support: CNPq and FAPESP