Concentration-dependent polarzed excitation,fluorescence and absorption spectra of Ti:Al2o3 crystals were measured at room temperature with the Ti3+ ion doped levels from 0.03 wt-% to 0.45 wt-%. Line shape distortion in polarized excitation spectra, indicated as the increasing of the intensity ratio of the shoulder to Peak and spectral broadering at longer wavelength side,were found as the Ti3+ ion concentration increased, whereas such phenomena did not emerge in the polarized absorption spectra at the same band. It is experimentally convinced that no Ti3+ ion pairs were formed even for the highestly doped sample in our experiment.