In this study, PVB/vermiculite nanocomposites were synthesised by in-situ reaction method using pristine vermiculite and its organoclays. Normally, organoclays for nanocomposites are prepared with cationic surfactants due to the charge distribution of clay minerals. Vermiculite has negative charges on the surfaces. Hence, cationic surfactant can easily penetrate to the interlayer spaces and extent them to the very high orders. However, the extension of interlayer spaces of vermiculite can also be satisfied with anionic surfactants in fact more than cationic surfactant does because of the exclusive incorporation of surfactants with vermiculite. Two different kinds, cationic and anionic, organoclays of vermiculite were synthesised to prepare PVB nanocomposites. The results revealed that exfoliated PVB/vermiculite nanocomposites achieved with anionic-organoclay, in contrast to common rules about clay-polymer nanocomposites. Exfoliation of anionic organoclays in PVB resulted in reduction of the total crystal structure of the clay minerals in the PVB which was also made the nanocomposites more elastic.