Objective:To explore the clinical significance of colposcopy in cervical atypical squamous cell of undetermined significance(ASCUS).Methods: Total of 516 women in our department were diagnosed with ASCUS by cytological test(TCT), they were further colposcope test. 209 cases of cervical intraepithelial neoplassia(CIN)were biopsied under the colposcope. In 307 cases of chronic cervicitis were given conservative therapy for 1-3 treatment cycles. Twelve cases of second TCT examination abnormal were biopsied under the colposcope. 295 cases of those with negative cytology checks take TCT regularly.Results: Of the 516 cases, 221 cases of cervical were biopsy (42.82%). Among them, 30 cases were chronic cervicitis , 185 cases were cervical intraepithelial neoplasia (CIN I-III), 6 case were squamous cell carcinoma, respectively. 295 cases without cervical biopsy, the follow-up of 6-18 months TCT found no abnormality.Conclusion: For the patients with cervical ASCUS, colposcopy associate with pathology biopsy may be helpful for the diagnosis and can provide a reasonable and effective treatment scheme for patients.