Abstract-Excitation spectra of CaF 2 , SrF 2 and BaF 2 crystals doped by CdF 2 , LaF 3 , YF 3 in vacuum ultraviolet region were investigated at liquid-helium temperature and at room temperature. Spectra of doped BaF 2 at low temperature and CaF 2 , SrF 2 at room temperature show significant decrease of excitation intensity against those in undoped crystals while the intensities in exciton regions remain nearly the same.The common reason of the suppression of exciton emission by impurity in alkaline-earth fluorides is unradiative electron-hole recombination on impurity sites.