For the first time we have combined sol-gel chemistry and millifluidic to generate silica ceramic engineering their sizes and aspect ratios. The particle sizes are controlled by varying the flow rates of the continuous and disperse phases within the home-made millifluidic reactor. Also, the silica particles aspect ratio can be tuned by adjusting the constrained geometry of the millifluidic devices, leading to the production of rod-like silica ceramics. Both SAXS and nitrogen physisorption measurements reveal that final inorganic silica ceramics are essentially microporous. (c) 2007 Elsevier B.V. All rights reserved.