Vitreous carbon (VC) is an excellent material for glass molding due to its high hot hardness and low adhesion to glass materials. As a low-cost VC micro/nano mold fabrication method, carbonization of replicated Furan precursor has been investigated for various glass molded micro/nano optical and fluidic devices. One of the critical issues identified in the method is the substantial pyrolysis shrinkage (~22%) during the carbonization process. In this study, a method of minimizing pyrolysis shrinkage by adding VC powder to the initial Furan resin mixture was investigated. The mixing ratio of Furan resin, initiator, and ethanol was experimentally optimized for each VC powder mixing ratio, and the effects of the VC powder mixing ratio on the pyrolysis shrinkage of VC mold were examined. As the VC powder mixing ratio increased from 0% to 40%, we observed a reduction in the shrinkage ratio from 22.18% to 12.89% aligning closely with theoretical expectations.