Syntheses of the heavy chalcogen-containing alumoxanes [(LAl)-L-Me(SeH)](2)(mu-O) (4) and ((LAl)-L-Me)(2)(mu-Te)(mu-O) (7) were accomplished by the reaction of ((LAlH)-L-Me)(2)(mu-O) (2; L-Me = HC[(CMe)N(2,4,6-Me3C6H2)](2)(-)) with either red selenium or metallic tellurium. The aluminum hydrogenselenide [(LAl)-L-Me(SeH)](2)(mu-Se) (3) was also prepared from the reaction of red selenium and (LAlH2)-L-Me (1). All compounds were characterized by spectroscopic methods and X-ray diffraction studies. Density functional theory calculations were performed on 4 and 7.