X-ray diffraction (XRD) and Raman spectra for a series of high-phosphorus-content GaN1-xPx films, with phosphorus content up to 15%, gr own by means of light-radiation heating, low-pressure metal-organic chemical vapor deposition have been investigated. XRD results show that (0002) peaks of GaN1-xPx samples have shifted to smaller angles compared with t hat of undoped GaN sample. The Raman spectra of GaN1-xPx films exh ibit four new vibrational modes compared with undoped GaN sample. These modes are assigned to gap modes related to the Ga—P bond vibrations, local vibrational mode related to the phosphorus clusters, and disorder-activated scattering, respectively. The frequency of the A1(LO) mode is found to decrease with incre asing x. This redshift is attributed to the effects of alloying and strain.