Two lanthanide(III) complexes with l-glutamate ligands [{Ln 2 (l-Glu) 2 (H 2 O) 8 }·4(ClO 4 )·2.5H 2 O] n (Ln=Gd (1), Eu (2)) have been prepared and characterized by single-crystal X-ray diffraction. The compounds are isomorphous with infinite cationic 2D layers stacked together by secondary bonds. The building blocks are slightly different non-centrosymmetric dinuclear units placed in alternating layers, the resulting structures thus containing four non-equivalent Ln metal sites. The dinuclear units contain a fourfold bridge, two in the η 1 :η 1 :μ 2 and two in the η 2 :η 1 :μ 2 modes, from two α- and two γ-carboxylates of four different l-Glu residues, respectively.