The feasibility of operation on a fluidized bed reactor (FBR) with inulinase imbedded in the gelatin alginate microspheres was investigated in order to improve the higher inulin conversion yields and enzyme stability than that of the previously obtained with the packed bed reactors. The operation processes were based on statistical analyses, the operational conditions of immobilized inulinase in a FBR system have been determined for immobilized enzyme load of 18 g, substrate concentration of 80 g/L, expansion ratio of 1.4 and substrate flow rate at 0.5 mL/min. According to the above-mentioned research parameters, the continuous fructose preparation with FBR system was sustainable for 10 days (240 h) and gained the productivity of 86.4 g/Ld. Compared with the previous results of the packed-bed reactor, the immobilized inulinase in the FBR system was applied in the inulin conversion, which appeared more effective. This study suggested that a system for the continuous and efficient enzymatic conversion of inulin in the FBR was founded, which could be potentially applicable for the scale-up production. Graphic Abstract The diagram of fluidized-bed reactor with immobilized inulinase for continuous inulin conversion [GRAPHICS] .