HPV structural antigens and HPV 6, 11, 16, 18 DNA sequences were detected with immunohistochemical staining and DNA dot blot hybridization in papillomas and squamous cell carcinomas of the throat and larynx. The positive rates of HPV antigens and HPV DNA sequences in 11 cases of papillomas were 45.5%, respectively, while the positive rates of HPV in 22 cases of squamous cell carcinomas were 22.7% and 27.3% respectively. The positive rates of HPV were in accord with those by histologic study in papilloma. The results indicate that the papillomas and squamous cell carcinomas of the throat and larynx may be related with HPV infection.