Infection with HPV 16 is believed to be a major risk factor for cervical cancer. To correlate HPV 16 infection and carcinogenesis in the cervix, we examined by ELISA 326 sera from healthy females and patients with cervical cancer, cervical intraepithelial neoplasia, or dysplasia, for the presence of IgG antibodies against HPV 16 virion protein L2 expressed in Escherichia coli. Whereas 2 of 208 were positive in the healthy females, 4 of 23 and 6 of 90 were positive in the patients with cervical cancer and dysplasia, respectively. The findings indicate that infection with HPV 16 is related to cancer and dysplasia of the cervix. The anti-L2 antibody did not occur coincidentally with the antibodies against the HPV 16 early proteins E4 and E7, which are specifically but independently associated with patients with cervical cancer.