By evaporation of an aqueous mixture of M(III) sulfate and diethanolammonium sulfate or triethanolammonium sulfate in the presence of sulfuric acid, double sulfates of Al(III) and Fe(III) were obtained. The stoichiometries of the compounds obtained were determined by means of elemental and TG analyses. It was found that they have the following general formulae : Al(HOCH2CH2)(2)NH2(SO4)(2) . 6H(2)O; Al(HOCH2CH2)(3)NH(SO4)(2) . 6H(2)O; Fe(HOCH2CH2)(2) NH2(SO4)(2) . 4H(2)O; Fe(HOCH2CH2)(3)NH(SO4)(2) . 6H(2)O. From the X-ray powder diffraction patterns, it was concluded that the investigated compounds have different crystal structures. It was also established, from the TG curves, that they lose water at low temperature and also that the anhydrous double salts decompose at low temperature (at about 523 K).