Three-dimensional organic microfabrication, an emerging technology, faces the challenge of lacking it sacrificial agent (SA) to temporarily support the formation of microscale geometries, which can he removed after a microstructure is constructed. In this study. an ultradense oil-in-organofluorine colloidal emulsion with photopolymerizable submicrometer droplets (diameter similar to 500 nm) was prepared and used as die required SA. Upon exposure to light, the colloidal emulsion undergoes a significant rheological change, which hardens the emulsion and presents the molding/protecting function that an SA must have. Importantly, the emulsion includes a synthesized fluorophilic/fluorophobic block copolymer surfactant to stabilize the droplet compartments, facilitating the dissolution of the postexposure SA. Two successfully built, complex, organic 3D microstructures show the effectiveness of using this novel SA material.