The semicontinuous production of blue pigment from gardenia fruit by immobilized cells of Bacillus subtilis KS-380 which excreted $eta$-glucosidase was investigated in comparison with free cells, . The blue pigment produced higher productivity under the conditions of aeration of 0.2m$ell$/min and 2mm diameter of gel beads by using 3.5% sodium alginate. Semicontinuous production by immobilized cell showed the highest productivity with replacement of fresh production medium in every 24hr for fourth fermentation cycle following the conditions of blue pigment productivity.