The spectra and amplitude–time characteristics of the radiation of studied Sn and Fe-doped Ga2O3 crystals excited with a runaway electron beam and an excilamp with a wavelength of 222 nm were investigated. The main contribution to the luminescence of samples in the region of 280–900 nm under excitation with a beam was shown to be made by cathodoluminescence. In the Fe-doped crystal, a new cathodeand photoluminescence band was detected within a wavelength range of 650–850 nm. In the Sn-doped crystal, Vavilov–Cherenkov radiation was detected in the region of 280–300 nm using a monochromator and a photomultiplier.