Continuous production of inulo-oligosaccharides from pure inulin was conducted using an immobilized endoinulinase reactor. The optimal operating conditions of the reactor for maximizing the productivity were as follows : 50 g/l of inulin feed concentration, pow rate as superficial space velocity 1.1 h(-1), and temperature 55 degrees C. The enzyme reactor was run for 15 d at 55 degrees C achieving an oligosaccharide yield of 83% without any significant loss of initial enzyme activity, during which the volumetric productivity was 55 g/lh and half life of the immobilized enzyme indicated 35 d.