A theoretical study of intra-cavity laser coofing bly anti-Stokes luminescence in a rare-earth doped glass is performed.Compared with cooling in an external cavity by multipassing the radiation,intra-cavity cooling has the advantage of high pumping power and high-absorbed power.However,one must ensure that the cavity can still form a laser by locating the material in the cavity.A roodel is developed to evaluate the enhancement factor and the absorbed power.The results show that for a low optical density,especially when the sample length is less than 2mm,the intracavity configuration is a very efficient method for laser cooling.The diode laser,which may become the best candidate for our model.is briefly discussed.