This study focused on the modification of montmorillonite (Mt) using the new modifying agent monoglyceride(M-Gly). M-Gly formed a self-assembled structure in Mt. interlayers, which may be used for further study in claymineral polymer nanocomposite (CPN) and cosmetic additives. The X-ray diffraction results showed the d001-value of Mt. increasing up to 16 Å in solvent and>60 Å in the melting method compared to 10 Å with neat Mt.This implies that when the melting method is applied using the internal thermomixer device with a high shearrate, the interlayer space of Mt. is expanded considerably. The transmission electron microscopy results showedthere was good dispersion of the organoclay layers in modified Mt. This means that the clay minerals layerstructure was disordered with two- or three-layer stacks that were separated after modification. The thermogravimetricanalysis also showed the thermal stability of the modified specimens in each method and evidencedthe insertion and elimination of M-Gly from the interlayer space of Mt. during the modification process.