Tissue specimens from 10 out of 12 patients with advanced epithelial ovarian adenocarcinoma contained DNA of human papillomavirus type 6 (HPV-6). HPV DNA was identified by in situ hybridization at high stringency using biotin-labeled DNA probes. Nonneoplastic tissue specimens from other pelvic sites of the same patients were also examined. None showed evidence of HPV DNA. The meaning of these findings in relation to epithelial ovarian carcinoma is discussed.