Dynamically vulcanized blends of polypropylene (PP) and styrene-ethylene-butadiene-styrene block copolymer (SEBS) with crosslinking coagent-assisted peroxide were prepared by melt blending to obtain SEBS/PP thermoplastic vulcanizates (TPVs). In addition to di-tert-butyl peroxide (DTBP), trimethylopropane trimethacrylate (TMPTMA) and poly(styrene-b- butadiene-bstyrene) (SBS) were used as the crosslinking coagents. TMPTMA and SBS showed synergistic effect on the properties of the TPVs. With the same dosage of DTBP and coagents, simultaneous loading of TMPTMA and SBS could generate the TPVs with shorter reaction time, higher solvent-resistance and better tensile properties than solely addition of TMPTMA or SBS. The synergistic effect mechanism of TMPTMA and SBS was also studied.