The Fragile Histidine Trind (FHIT) is a tumor suppressor gene at chromosome 3p14. 2 that has identified by positional cloning . The mechanisms for inactivating the gene have been revealed to deletions , aderrant transcripts and methyla-tion of the 5′CpG-island. The tumor suppressor effect is probably related with inducing cell apoptosis, cell cycle retardation , diadenosine 5′,5″-p1 ,p3 - triphosphate hydrolase, tubulin and ubiquitin conjugase. FHIT gene deletion and abnormal expression in early stage esophageal carcinoma suggest that FHIT may play a key role in the carcinogenesis and progression of human esophageal cancers.