The PVC composite was prepared by extrusion melt using a new plasticizer octodecyl acyl tributyl citrate and PVC resin. Influence on mechanical and resistance to cold properties of PVC was studied by tensile and low temperature impact tests. The thermal behavior, texture and mechanism of plasticizing of OTBC plastifying PVC were supported by TG, DSC and SEM. The result indicated that the glass transition temperature of plastifying material was about 36°C, breaking strength was 25.3MPa, elongation at break was 250% and, plasicizing efficiency was 0.88, resistance to cold property better than plastifying material of DOP's, domains between two phases of micro-texture were small and distributed homogeneously when OTBC content in PVC resin was 30%. © (2011) Trans Tech Publications, Switzerland.