A new process for the immobilization of sodium alginate, which employs a vibration of membrane induced by sound waves from a horn-type speaker, is developed to produce uniformly-sized beads of predictable diameter. Frequency of sound wave and production rate are varied to find the optimal control ranges for the bead production. The controllable bead size range is 1.50-3.50 mm and the experimental production rates are 0-12 dm(3) h(-1) by a single nozzle. This method of bead production is a practical alternative to conventional continuous bead production methods with low apparatus cost and easier and better control of bead size and shape.