U-, n- and p-GaN∶Er films were prepared by ion implantation method. Three carrier types of samples were studied by Raman spectra analysis. After Er+ ion implantation into GaN samples, new Raman peaks at wavenumber of 293, 362和670 cm-1 appeared, where 293 cm-1 was considered as disordered activation of Raman scattering (DARS), 362 and 670 cm-1 may be associated with GaN lattice defects formed after ion implantation. The E2 (high) characteristic peak moves to the high frequency before and after GaN∶Er samples annealing at 800 ℃, indicating that GaN lattice is under the compressive stress. The Lorenz fitting was used to analysed the occurrences of A1(LO) peak in different samples which is composed of the uncoupled mode LO and the plasmon coupling mode LPP+, qualitatively pointing out the carrier concentration variation of a series of GaN∶Er samples.