Nd:MgO:LiNbO3 waveguides have been fabricated by proton-exchange method. To obtain the atomic composition profiles of the waveguide, the SIMS (second ion mass spectrum) of the planer waveguide was measured. The absorption spectra of Nd:MgO:LiNbO3 crystal and the fluorescence spectra induced in the channel waveguide and subetrate were measured respectively.