A simple and mass producible method was developed to incorporate multiwalled carbon nanotubes (MWCNTs) into electrospun silk fibroin (Bombyx mori) nanofibers. The process consists of dispersing the acid-treated MWCNTs in an aqueous silk fibroin solution, and blending this solution with a water-soluble polymer, poly(ethylene oxide) (PEO), followed by electrospinning of the composite solution. The morphology and microstructure of the electrospun nanofibers were characterized using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The FESEM and TEM images show that the MWCNTs are embedded along the nanofibers. Aqueous-based electrospinning of silk/PEO/MWCNTs composites provides potentially useful options for the fabrication of biomaterial scaffolds, e.g. wound dressings, based on this unique fibrous protein.