Abstract: ob＜x＞jective To investigate the ex＜x＞pression of HER-2/neu protein in human colon cancer tissues and its relationship with clinical pathology. Methods Immunohistochemistry was used to detect the ex＜x＞pression of HER-2/neu protein in 79 specimens of human colon cancer tissues and adjacent tissues. Results The ex＜x＞pression of HER-2/neu was significantly higher in cancer tissues than in adjacent tissues ( P<0.05). The positive rate of HER-2/neu was significantly higher in Dukes C, D and lymph node me＜x＞tastasis than Dukes A and B Stage and no lymph node me＜x＞tastasis (P<0.05). Conclusion HER-2/neu is highly expressed in colon cancer tissues, suggesting that HER-2/neu can be used as a marker for the diagnosis and prognosis of colon cancer.