Influence of blend mode of extender oil on the properties of thermoplastic vulcanizates (TPV), based on an ethylene-propylene-diene copolymer (EPDM) and a polypropylene (PP), was studied. The EPDM/PP TPVs were prepared in an open roll mill using two different modes in blending sequence of paraffinic oil and phenolic curative, i.e., Oil-Cure and Cure-Oil modes. Degree of cross-linking by gel fraction and properties such as hardness, tensile strength, elongation at break, and melt flow rate were investigated as a function of extender oil content for the two modes. Little influence of the blend mode of extender oil on the degree of cross-linking and mechancial behaviors was observed. However, the use of Cure-Oil mode in the preparation of EPDM/PP TPVs resulted in a marked incrase in the level of processability as reflected by melt flow index, as compared to the use of Oil-Cure mode.