The paper reports that InP epitaxial layers were grown on iron doped semi-insulating GaAs substrate by low-pressure metalorganic chemical vapor decomposition (LP-MOCVD). Prior to the growth of InP, amorphous InP buffer layer was grown at 400°C, then the substrate zone temperature was raised to the normal InP growth temperature and InP epitaxial layer was grown at 665°C. The obtained InP layers have been characterized by transmission electron microscope, optical microscope, X-ray diffraction, photoluminescence measurement.