The halogen-free resin composition comprises (A) 100 parts by weight of cyanate ester resin; (B) 5 to 50 parts by weight of styrene-maleic anhydride; (C) 5 to 100 parts by weight of polyphenylene oxide resin; (D) 10 to 150 parts by weight of phosphazene; and (E) 10 to 1000 parts by weight of inorganic filler. By using specific components at specific proportions, the halogen-free resin composition offers the features of low dielectric constant, low dissipation factor, high heat resistance and high flame retardancy, and can be made into prepreg or resin film, and thereby used in copper clad laminate or printed circuit board.