Abstract: The present invention relates to an epoxy resin composition, and a prepreg and a copper clad laminate made therefrom. The epoxy resin composition comprises: (A) epoxy resin containing two or over two epoxy groups, (B) active ester curing agent, and (C) phosphate salt compound. The epoxy resin composition of the present invention adopts epoxy resin with specific molecular structure, which has comparatively high functionality, so the cured products have high glass transition temperature and low hydroscopic property; active ester is adopted as the curing agent to make full use of the advantages that polar groups will not be produced when the active ester reacts with the epoxy resin; the prepreg and copper clad laminate made therefrom of the present invention can achieve halogen-free flame retardance, and meanwhile have excellent dielectric properties and good resistance to humidity and heat.