Abstract: Objective To investigate Proliferating cell nuclear antigen(PCNA) and DNA index(DI) correlation to biological characteristics of laryngeal carcinoma and their values of clinical prognosis. Methods Immunohistochemical staining was used to detect the expression of PCNA in laryngeal cancer and normal tissue,and with MIPS-I image analysis system DNA contents of cancer cell were measured and made out DNA index. Results PCNA positive rate was 100% in laryngeal carcinoma,and it was negative in all 10 normal laryngeal mucosa specimens(P<0.01).The positive expression of PCNA and DNA contents in the laryngeal carcinoma were increased with the differentiation of tumors lower(P<0.05).With the increasing PCNA positive expression and DI,the prognosis of the patients got poorer(P<0.05). Conclusion PCNA and DI were simultaneously detected can be used as the prediction of tumor malignancy and prognosis.