The spectra of steady-state and time-resolved cathodoluminescence have been measured at 5.4 K for α-Al2O3 single crystals irradiated by fast neutrons with the same dose of 6.9 × 1018 cm−2 and then preheated to certain temperatures from 295 K to 1250 K. The analysis of these spectra allows to conclude that irradiation decreases the intensity of the 7.6-eV intrinsic emission related to self-trapped excitons by about 80 times and practically suppresses infrared Cr3+ impurity emission, while the enhancement of luminescence at 2–4.2 eV is connected with the creation of single F-type centers (oxygen vacancy with two or one trapped electrons) and their F2-type dimers in different charge states. The following evolution of the above-mentioned emission bands with the increase of preheating temperature is determined by the decreasing concentration of the F and F2 defects, partial reabsorption of luminescence as well as varied efficiency of nonradiative processes, in which electron-hole pairs formed by an electron beam are involved. The limitations of the use of specific cathodoluminescence bands for the detection of radiation damage and its further recovery via thermal annealing are considered.