This study reports on the fabrication of BST (Ba0.6Sr0.4TiO3)-based 3D microcomponents through an aqueous colloidal approach. The BST powder was synthesized by solid-state reaction assisted by thermal analysis and XRD diffraction. Well crystalline cubic BST single phase was obtained upon heat-treating the precursor powder mixture at 1200°C–1250°C. The reactivity of the BST powder toward water was evaluated by the changes in pH and concentration of leached ionic species along aging time. Hydrolysis reactions were suppressed by chemisorbing a suitable phosphate-based protective agent and enabled an excellent dispersion ability to be achieved. Aqueous suspensions with solids loadings as high as 50 vol% that are stable against hydrolysis for several days could easily be prepared from the surface-treated BST powder in aqueous solutions of an epoxy resin. After adding a suitable hardener, the colloidal suspensions could easily be cast into soft silicon rubber molds to obtain homogeneous and high dense green BST bodies.