Our objective in this work consists in the synthesis, the characterization, the elaboration, the formulation, and the rheological study of the new phosphoric epoxy resin: pentaglycidyl ether pentaphenoxy of phosphorus (PGEPPP). Thus, we identified this polymer by Fourier transform infrared spectroscopy. Then, its chemical structure was confirmed by nuclear magnetic resonance of proton (H-1 NMR) and carbon (C-13 NMR). Furthermore, the rheological analyzes of the epoxy resin and their composite (PGEPPP/MDA/PN) were determined by the RHM01-RD HAAKE rheometer. Moreover, this epoxy polymer and their composite have been applied in flow phenomena and implementation. Finally, we proceeded to the morphological of the composite (PGEPPP/MDA/PN) using the scanning electron microscope, in order to confirm the dispersion of the natural phosphate load incorporated into the prepared composite.