Silk fabric was pretreated with 3-aminopropyltrimethoxysilane (silane) in supercritical carbon dioxide and then silver nanoparticles were synthesized on the pretreated silk fabric under microwave irradiation. The silver nanoparticle coated fabrics were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and ultraviolet–visible spectroscopy. Deposition rate and color characteristics of the silver coating of samples were investigated. The results show that silver-coated silk fabric with pretreatment of the silane via supercritical carbon dioxide possesses excellent ultraviolet protection, softness and the adhesive strength between silver coating and silk fabric is improved.