Two kinds of room temperature ionic liquids, [bmim]PF6 (1-butyl-3-methylimidazolium hexafluorophosphate) and [hmim]PF6 (1-hexyl-3-methylimidazolium hexafluorophosphate), were respectively used as plasticizer for PVC paste resin. The mechanical properties, thermal and ultraviolet ray stabilities, and migration characteristics of the PVC paste resin samples were determined by universal testing machine, TG/DTA, and HPLC. The results showed that the tensile strength and elastic modulus decreased, the elongation at break and thermal stability of PVC paste resin membranes were improved with the increasing of [bmim]PF6 or [hmim]PF6 dosages. The immersed time and temperature could accelerate leaching and migration of plasticizers in plasticized PVC paste resin films. Moreover, the effect of solvent environment on migration amount was also studied.