Here, a stable multilayered adduct maghemite/surfactant/clay, gamma-Fe2O3/CTAB/Clay with sandwich-like nanostructure, has been synthesized by electrostatic self-assembly between exfoliated sodium montmorillonite nanoplatelets and substituted gamma-Fe2O3/CTAB cationic polyelectrolytes, in which sodium montmorillonite particles are exfoliated by means of extensive swelling and gamma-Fe2O3/CTAB polyelectrolytes are obtained by sonicating gamma-Fe2O3 nanoparticles in CTAB water suspension. This sample, with the interlamellar spacing of 34.24 angstrom, exhibits a high ordered structure, which is well manifested by low-angle X-ray powder diffraction (LXRD) patterns. IR spectroscopy and thermogravimetric (TG) analysis are carried out to characterize its composition and thermal stability. Furthermore, zero-field Mossbauer spectroscopy unveils its magnetism and the nature of iron oxide. The successful combination of both the monodispersed functional components and the clay platelets shows the promise for self-assembly of the stable multilayer adduct and the versatility of this approach. (c) 2005 Elsevier B.V. All rights reserved.