Abstract: The development of gastric cancer is a result of a multi gene genetic and epigenetic common function. DKK3(dickkopf-3) is a newly discovered tumor suppressor gene and an antagonist of the classic Wnt signaling pathway. DKK3 protein inactivation and Wnt signal pathway abnormal activation can lead to tumor occurrence. The silence of DKK3 gene expression is a frequent event of gastric cancer, which was usually caused by the promoter methylation, and significantly correlateswith the prognosis of gastric cancer.