A novel intumescent flame retardant system based on shell (S) and histidine diphosphate (HF) was developed and introduced into the epoxy resin in order to verify its effectiveness in the inhibition of the burning process. To confirm the structure of HF, powder X-ray diffraction (XRD) was used. The influence of the flame retardant system on the burning and smoke emission of the resin was assessed based on cone calorimeter (CC) measurements. Moreover, structural evaluation of polymeric materials was carried out using scanning electron microscopy (SEM). It was found that the incorporation of the developed flame retardant system caused the formation of a protective layer in the form of char, which reduced burning process and smoke emission of the epoxy resin. The obtained results were better than those generated by commercial intumescent fire retardant.