Abstract: Abstract　 Objective: To investigate the relationship between the CXCL12-CXCR4 biological axis and lymph node metastasis in papillary thyroid cancer. Methods: Expression of CXCR4 and CXCL12 mRNA in 72 fresh tumorous tissue samples of papillary thyroid cancer and lymph node tissues was determined using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), while CXCR4 protein expression was measured in 52 formalin-fixed paraffin-embedded tissue sections by immunohistochemistry. Results: Expression of CXCR4 mRNA and protein was elevated in the papillary thyroid cancer and in the metastatic tissues. The expression was significantly higher in the patient subgroup with lymph node metastasis than in the subgroup without lymph node metastasis ( P < 0.05 ). There was also elevated expression of CXCL12 mRNA and protein in the cervical lymph node tissues but no statistical differences were found between the subgroup with lymph node metastasis and that without lymph node metastasis ( P >0.05 ). Conclusion: The expression of CXCR4 and CXCL12 was significantly correlated with lymph node metastasis in papillary thyroid cancer, indicating that the CXCL12-CXCR4 biological axis can play an important role in the nodal metastasis of papillary thyroid cancer. CXCR4 is a potential therapeutic target to restrain metastasis.