Reactions of CeCl3·6H2O and Gd(NO3)3·5H2O with biacetyl bis(benzoylhydrazone) (H2babh) and KOH in 1:2:2 mole ratio in methanol afford the complexes [Ce(babh)2] (1) and [Gd(babh)(Hbabh)]·H2O (2·H2O), respectively in good yields. Characterization of the complexes has been performed with the help of elemental analysis, magnetic susceptibility, spectroscopic (IR, UV-Vis, EPR and NMR) and X-ray crystallo-graphic measurements. 1 is diamagnetic and NMR active, while 2·H2O is paramagnetic (𝜇eff = 8.03 𝜇B at 300 K) and EPR active. The complexes crystallize as 1·CH2Cl2 and 2·H2O. X-ray structures show that the metal centre in each of 1 and 2 is in a distorted dodecahedral N4O4 coordination sphere assembled by two meridionally spanning ONNO-donor ligands. Self-assembly of 1·CH2Cl2 via intermolecular C−H···N and C−H···Cl hydrogen bonds and 𝜋-𝜋 interactions provides one-dimensional ‘ladder’ type structure. On the other hand, 2·H2O assembles into a two-dimensional ‘sheet’ like network through intermolecular N−H···O and O−H···N hydrogen bonds.