The crystal structure of [Er(Gly)2 (HaO)4]2(ClO4)6.4(Dio) (Gly= NH2CH2COOH; Dio=dioxane) has been determined belonging to triclinic system with space group P1.The final R was 0.055. The carboxyl groups of Gly are associated to Er(Ⅲ) atoms to act as the bidentate bridging ligands.