A method was developed to prepare silk fibroin microspheres using lipid vesicles as templates to efficiently load therapeutic agents in active form for controlled release. The lipids are subsequently removed through the use of a dehydration agent, such as methanol or sodium chloride, resulting in β-sheet structure dominant silk microsphere structures having about 2 μm in diameter. The therapeutic agent can be entrapped in the silk microspheres and used in pharmaceutical formulations for controlled-release treatments.