A halogen-free resin composition is provided, comprising: (A) one or more phosphorous-containing epoxy resins; (B) a hardener; and (C) a hardening accelerator, wherein the hardener of component (B) has the structure represented by the following formula (I): ##STR00001## wherein, each symbol is defined as in the specification. The halogen-free resin composition of the present invention has excellent thermal resistance and flame retardant property, and is thereby suitably useful in the application of adhesives, composite materials, laminated plates, printed circuit boards, copper foil adhesives, inks used for build-up process, semiconductor packaging materials, and the like.