Abstract: Using fumaric acid, pentaerythritol acid and lanthanum acetate as raw materials, rare earth compounds of pentaerythritol fumarate lanthanum (FGPE-LA) were synthesized, the structure and composition of FGPE-La were characterized by IR, XPS, elemental analysis and rare earth content analysis. The thermal stability and antibacterial properties of FGPE-La in PVC were studied. The results show that FGPE-La is a multi-functional additive for PVC with both thermal stability and antibacterial properties. When FGPE-La: znst2 = 3:1 is used together, it has good initial whiteness and long-term thermal stability, when 4 parts of FGPE-La were used alone, the plasticizing efficiency was obviously improved, and the heat stabilization time was 68 minutes, which could significantly improve the long-term stability of PVC. This is mainly because FGPE-La can absorb HCl produced by the degradation of PVC, and can effectively complexate with ZNCL2 to prevent the“Zinc burn” phenomenon. When 6% fgpe-la was added, the bacteriostasis rate was 99.1% , and the hemolysis rate was only 4.6% , which showed that fgpe-la had good Biocompatibility. SEM analysis showed that FGPE-La could change the lipid part of the membrane and destroy the cell structure, thus achieving the antibacterial effect.