Among genital human papillomaviruses (HPVs), the so-called high-risk (HPV 16, 18, etc.) and intermediate-risk (HPV 58, etc.) viruses are believed to be etiologically associated with cervical cancer. To estimate the extent of infection with common HPVs among Japanese females, we examined 328 sera from healthy donors (201) and patients with cervical intraepithelial neoplasia (CIN) (22), cervical cancer (67), and condyloma acuminatum (CA) (38) for IgG antibodies against L1 capsid protein by enzyme-linked immunosorbent assay using virus-like particles of HPVs 16, 18, 58 and 6b (low-risk) as antigens. Antibodies recognizing conformational epitopes were found in the sera from both the patients and the healthy donors. The prevalences of anti-HPV 16, 18, and 58 antibodies in the sera from the patients with CIN (45%) and cervical cancer (49%), and that of anti-HPV 6b in the sera from the patients with CA (55%), were significantly higher than those in the sera from the age-matched healthy donors (12%, 14%, and 23%, respectively). Anti-HPV 16 was not found in some of the sera from patients with HPV 16-DNA positive CIN or cervical cancer, suggesting that HPV infection may not always induce production of anti-capsid antibodies or that the level of antibodies may not always be maintained until development of CIN or cancer. Some of the sera contained antibodies against more than one type of HPV, suggesting that the donors had been infected with different HPVs. The type-specific antibodies against capsid L1 protein of one type of HPV may not be able to prevent infections with other types of HPVs.