OBJECTIVE: This study was performed to investigate the efficacy of DNA chip method for detecting and genotyping of human papillomavirus (HPV) and screening of high-grade CIN (cervical intraepithelial neoplasia) or invasive cancer in the patients with atypical squamous cells of undetermined significance (ASC-US). METHODS: This study was based on 131 cases to be revealed ASC-US by Pap smear for the cervical cancer screening from July 2004 to Octorber 2004. They were evaluated by HPV DNA chip test, Cervical colposcopy and directed biopsy, and cone biopsy. The results of type 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 54, 56, 58, 59, 66 and 68 in HPV DNA chip test were categorized as high risk HPV. We evaluate the detection rate of the high-grade CIN and invasive cancer by HPV DNA chip test. RESULTS: The incidence of high risk HPV DNA was 51.1% (67/131). Twelve of 131 (9.2%) were diagnosed as high-grade CIN or CIS on histology. The detection rate of high risk HPV DNA in high-grade CIN and invasive cancer was 83.3% (10/12). The detection rate of high risk HPV DNA was 36.0% (31/86) in normal or reactive, and 83.3% (10/12) in CIN II or above on histology. Higher the grade of biopsy, more the detection rate of high risk HPV DNA by HPV DNA chip test. CONCLUSION: The use of HPV DNA chip test in patients with ASC-US may be useful in detection of high-grade CIN or invasive cancer.