Reactions of ligand 5-(1H-imidazol-4-yl)methylaminoisophthalic acid (H 3 L) with varied lanthanide metal salts led to the formation of five scalelike 2D layered complexes {[Ln(H 2 L)(HL)(H 2 O) 2 ]·H 2 O} n [Ln(III)=Pr(III) (1), Nd(III) (2), Sm(III) (3), Gd(III) (4), Tb(III) (5)]. The single crystal X-ray diffraction analyses revealed that five complexes crystallized in the same monoclinic space group C2/c are isomorphous and isostructural, and the 2D networks are further connected by hydrogen bonds and π–π interactions resulting in formation of 3D structures. Investigations on the visible luminescent property of the complexes demonstrate that compounds 3 and 5 show characteristic emissions of Sm(III) and Tb(III) in the solid state at room temperature, respectively.