This work describes the synthesis and characterization of new poly(o-phenylenediamine (PoPD)/modified-clay nanocomposite materials. For the synthesis, the raw clay (named as Mag) used in this study was from Maghnia (west Algeria), (Mag) clay was ion-exchanged with cobalt(II) sulfate hydrate and copper sulfate. The modified-clays were then dispersed in a oPD monomer-containing acidic solution to carry out in-situ intercalative oxidative polymerization by ammonium persulfate. XRF and XRD characterization reveal the success of ion-exchange to form highly intercalated Mag-Co and Mag-Cu clays. After polymerization, the disappearance of the interlayer-spacing diffraction peak for the PoPD-Mag-Cu and PoPD-Mag-Co nanocomposites points out fully exfoliation of the clay structure. The formation of intercalated PoPD into modified-clay nanocomposites was confirmed by XRD, TEM, TG analysis, FTIR spectroscopy and UV-vis studies. The nanocomposites show optical properties and the redox processes observed by cyclic voltammetry indicate that the reported polymerization into modified-clays leads to electroactive hybrid materials. All these properties make these polymer/clay nanocomposites attractive materials for multiple applications.