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