With advantages of flame retardant, insulation, corrosion resistance, wear resistance and low cost, wide raw material source, Polyvinyl chloride (PVC) has excellent comprehensive performance. However, in the application of PVC, the impact strength is low and the thermal stability in processing is poor, which limits its application in the field of functional materials. In order to further improve its comprehensive performance, the study choose polyurethane elastomeric (TPU) to toughening modification. The main research purpose of this experiment is design formula to compound polyester TPU. Using diphenyl methane diisocyanate (MDI), poly-caprolaclone glycol (PCL), and 1,4-butanediol (1,4-BDO) as raw materials.Under the condition of isocyanate index (R=0.98), reaction temperature(T=60~70 �Ž), reaction time(t=1 h) design formula. Through infrared spectroscopy (FTIR), NMR, elemental analysis, nuclear magnetic resonance, differential scanning calorimetry (DSC) and gel chromatograph surveying its molecular weight, determine the hard segment content of TPU and chemical structure. By blending with PVC, we evaluate the toughening effect of synthetic TPU to PVC. Through the mechanics performance test, DSC and SEM to characterize the structure properties of the blending material, reveal the toughening mechanism. Results show that there is a good compatibility between the synthesized TPU and PVC. Compared with the commercially TPU brand screening by blending experiments, which has a good effect on PVC toughening modification. When PVC:TPU = 170:30, mechanical performance reached the best level, and toughening effect exceed commercially available brand TPU; When PVC:TPU:CPE=170:15:15, the mechanical properties is optimal; Respectively adding light CaCO3 and heavy CaCO3, reached the goal that toughening and strengthening PVC.