To evaluate the prognostic significance of gene amplification and overexpression of cyclin D1 in the patients of esophageal squamous cancer, slot blot hybridization and immunohistochemical staining were performed. The patients with gene amplification or overexpression of cyclin D1 were significantly poorly prognosis than patients these were negative. And to investigate abnormality of p16 and p15 genes in 12 squamous cell carcinoma of esophagus, PCR and SSCP analysis were performed. In only one of 12 tumors, complete deletion of p16 and p15 genes was detected. But in other 11 tumors, no abnormality could be detected. Besides to evaluate the prognostic significance of expression of p16 in patients of esophageal squamous cancer, immunohistochemical staining for p16 was performed. The patients with overexpression of p16 were significantly better prognosis than patients that was negative, and this result was opposite contrast with the result of cyclin D1.