Abstract: In acrylamide gel system mesocarbon microbeads (MCMB) were used as carbon source to prepared carbon materials by gelcasting process.Adding MCMB in batches and ball milling were used to increase the MCMB contents in the sizing.The influences of gelcasting process on the dispersibility,viscosity,solid content and gel reaction,solidification and drying for MCMB sizing were analyzed.The results show that when the dispersant content was 1wt.% of MCMB and the pH value was 13,MCMB particles in the water based sizing distributed evenly and was stable.The solid content in the sizing can be increased after adding MCMB in batches and ball milling treatment,the maximum of which was 75wt.% with the highest viscosity of 1.822 Pa·s for the sizing.Gel induction time and reaction time could reduce quickly when adding more initiator,while the influence of catalyst content was not obvious.Finally,0.4 mL initiator and 0.6 mL catalyst in 30 mL sizing were suitable.Vacuum degassing before casting the sizing and displacement of water in wet green body with alcohol during the initial stage of dry processing were necessary for preparing carbon green body with smooth and crack-free surface.