This study reports drug-loaded silk sericin (SS)/silk fibroin (SF) blend microparticles being fabricated by the water-in-oil emulsion solvent diffusion of a SS/SF aqueous blend solution. Blue dextran was used as the water-soluble drug model. The influence of the SS/SF blend ratio on the characteristics and drug release behavior of the blend microparticles was investigated. The blend microparticles were analyzed by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and UV-vis spectroscopy. The blend microparticles were nearly spherical in shape as determined from SEM micrographs. The FTIR and TG results demonstrated that interactions between SS and SF molecules had occurred. The blend microparticles showed very high drug loading efficiency (94-98%) for all blend ratios. The in vitro drug release significantly decreased with decreasing SS blend ratio. The results demonstrated that the SS/SF blend microparticles could be used as biocompatible and biodegradable microparticles for controlled release drug delivery applications.