Abstract: Abstract：The rare earth stabilizers of lanthanum myristate, cerium myristate and neodymium myristate were synthesized. Novel rare earth myristate compound thermal stabilizers for rigid PVC were prepared from lanthanum (cerium/neodymium) myristate, zinc/calcium stearate, pentaerythritol and investigated by the Congo red method. Influence of these stabilizers on PVC was determined by means of torque rheometer process tests and dynamic mechanics spectrometer. The result showed that rare earth compound thermal stabilizers had good thermal stability. Static and dynamic thermal stability time could reach about 120 min and 60 min. The early coloring of PVC was restrained better. Processing performance of rare earth compound thermal stabilizers were better than lead salt system. The tensile strength, tensile strain at break and fracture strength were similar to lead salt system, while the impact strength was higher.