We demonstrated a direct approach to encapsulate sub-micron oil or aqueous microspheres by interfacial reaction on oil-in-water (O/W) or water-in-oil (W/O) inverse emulsion templates. O/W or W/O inverse emulsions were stabilized by the commercially available triblock copolymers, Pluronics. The formation of oil-core or aqueous-core poly(ethylene oxide)/silica capsules was confirmed by transmission electron microscopy observations. Shell thickness of capsules can be finely tuned by adjusting amount of tetraethoxysilane loadings. The encapsulation and release properties of capsules were investigated. The principle and concept behind this technique are informative and have broad potential applications in the fields of encapsulation and controlled release.