The Raman back scattering/channeling technique was used to analyze the damage recovery at different annealing temperatures and to determine the lattice locatio n of the Er-implanted GaN samples. A better damage recovery was observed with in creasing annealing temperature below 1000℃, but a complete recovery of the impl antation damage cannot be achieved. For a sample annealed for at 900℃ 30 min th e Er and Ga angular scans across the axis was measured, indicating that a bout 76% of Er ions occupies substitutional sites. Moreover, the photoluminscenc e (PL) properties of Er-implanted GaN thin films have been also studied. The exp erimental results indicate that those samples annealed at a higher temperature b elow 1000℃ had a stronger 1539nm PL intensity. The thermal quenching of PL inte nsity for samples annealed at 900℃ measured at temperatures from 15K to 300K is 30%.