We analyzed the clonality and human papillomavirus (HPV) infection status of concurrent glandular and squamous lesions and adenosquamous carcinomas of the uterine cervix to clarify their histogenesis. The glandular and squamous components were clonally different from each other in 7 informative concurrent lesions. HPV was episomal in 2 polyclonal glandular dysplasias (GDs). HPV was in a mixed integrated-episomal form in a monoclonal GD, an adenocarcinoma in situ, and an adenocarcinoma. Both tumor components were monoclonal in origin in 6 adenosquamous carcinomas, with identical patterns of X-chromosomal inactivation and types and physical status of HPV. These results imply that the concurrent glandular and squamous lesions are formed separately, whereas adenosquamous carcinoma is more likely to be a combination tumor of monoclonal origin, and that integration of HPV has an important role in the progression from polyclonal GD through monoclonal expansion to adenocarcinoma in situ and adenocarcinoma.