The work aims to find a suitable vulcanizing agent to prepare poly(lactic acid) (PLA)-based dynamic vulcanizates (TPV) with good resilience. With acrylic rubber (ACM) as a rubbery phase, trithiocyanuric acid (TCY), hexamethylene diamine carbamate (HDC), and N,N’-dicinnamal-1,6-hexamethylenediamine (DHD) were respectively used as a vulcanizing agent for ACM/PLA blend system. The variation of torque curves of these three vulcanizing agents with ACM or PLA during melt-compounding was analyzed. TCY was found to be the most suitable vulcanizing agent for the ACM/PLA TPV system among these three vulcanizing agents. When the content of TCY was 0.75 g, the hardness of TPV was moderate, the tensile strength was high and the elongation at break was similar to others, but the rate of the permanent deformation was the smallest, only 26%. After addition of TCY, the morphology of rubbery phase in the TPV materials was changed from the original spherical shape to the cylindrical one, distributed in PLA matrix. TCY can be used as vulcanizing agent to prepare PLA-based TPV with good mechanical properties.