With the introduction of glycidyl methacrylate (GMA) and allyloxy hydroxyl propanesulfonic salt (AHPS) to the waterborne polyurethane/polyacylate (WPUA) emulsion, a stable epoxy-modified waterborne polyurethane/polyacylate (EPUAS) composite emulsion with high solid content had been obtained. The structure and morphology were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM) and X-ray diffraction (XRD). The GMA content and the AHPS content on properties of the emulsion and films were discussed. The FTIR results showed that GMA and AHPS both reacted with WPUA. A core-shell structure is observed by TEM. The properties of EPUAS emulsion and films were improved by modification.