The deep center-related photoluminescence(PL)in GaAs thin films grown onSi substrates were measured with respect to the changes of temperature. The peak energiesand PL intensities of the 0. 78 eV, 0. 84 eV and 0. 93 eV PL bands as a function oftemperature were studied. It is found that the temperature dependence of the PLintensities obeys the formula as that used for amorphous semiconductors because of theexistonce of localized states. The origins of the PL bands were discussed.