PURPOSE: The aim of this study is to confirm the association of human papillomavirus with colorectal cancer. METHODS: We studied 44 patients who were received operation for colorectal cancer from 1, Jan. 1997 to 31, Dec. at Korea University Guro Hospital. We used paraffin- embedded tissue sections of colorectal adenocarcinomas and human cervical cell lines as a positive control. We also studied 10 cases of anal canal squamous cell carcinomas. The extracted DNA were analyzed by polymerase chain reaction and enzyme restriction method. RESULTS: Human papillomavirus DNA was not detected in all specimen of colorectal adenocarcinomas. But in 3 of 10 (30%) of anal canal squamous carcinomas, human papillomavirus DNA was detected. We identified this human papillomvirus DNA as type 16 by enzyme restriction technique. CONCLUSIONS: Human papillomavirus usually associated with malignant transformation are present in anal canal squamous cell carcinomas. This study also showed same result. But this association was absent from adenocarcinoma of the colon and rectum.