The rate of cellulose production by Acetobacter pasteurianus AP-1SK was about five times higher in a static culture than in stirred or shaken cultures. To increase the rate of production of bacterial cellulose (BC) in static culture further, a system was developed in which cellulose pellicles were formed on an oxygen-permeable synthetic membrane and on a liquid surface. The rate of BC production was doubled using the cylindrical vessel, of which the bottom end was covered with a silicone sheet of 100 mu m thickness. A silicone air bag was also used to produce BC. During this study we found that the rate of cellulose production on a silicone membrane depended strongly on the degree of roughness of the membrane surface. The rate of BC production was about five times higher on a glossy surface of a silicone membrane than on an embossed surface of one. The mechanism was discussed based on experimental results for surface-processed silicone membranes.