Abstract: Mechanical and Damping properties of cyanate modified epoxy/glass fibre composites are investigated under varied temperatures. The tensile properties are investigated using UTM. The increase in tensile strength of cyanate modified epoxy system with increase in cyanate loading is 320-401 MPa. Free vibration method is used to experimentally measure frequency response and damping factor. The viscoelastic properties such as storage modulus (E’), loss modulus (E’=) and stiffness (K) were obtained for cyanate modified epoxy/glass fibre composites.