This study explored an approach to suppress plasticizer DOP migrating from flexible PVC. MMT/PVC composite materials were prepared using MMT modified by CH3(CH2)17NH3+, and tortuous paths for DOP were created by MMT dispersion in PVC matrix. Short time soaking in hexane treatment on PVC specimen formed two membranes that did not contain DOP on the PVC surface, which came into being barrier for DOP molecules. DOP migration tests showed that hexane-treated PVC’s migration curve presented time lag compared to that of none-treated neat PVC, and migration rate of hexane-treated MMT/PVC was much lower than the reference. Hexane-treated MMT-2/PVC sample exhibited the best performance on the prevention of DOP migration.