OBJECTIVE: The purpose of this study was to evaluate the efficacy of loop electrosurgical excision procedure which can be done safely and efficiently in the out-patient setting for the diagnosis and treatment of uterine cervical dysplasia. MATERIALS AND METHODS: Retrospective review of 42 patients with the uterine cervical dysplasia who underwent LEEP at the Department of Ob & Gyn in Korea University Ansan Hospital from Jan. 1998 to Dec. 2000. The diagnostic accuracy among cytology, punch biopsy, and LEEP was investigated. Also, we interpreted margin status relation to residual tumor after conization and hysterectomy. We used the hybrid capture II test, with the Digene Cervical Sampler(Digene Corporation, Gaithersburg, MD, USA), for high risk HPV DNA(HPV 16, 18 subtype) detection. RESULTS: Cervical cytologic results were underestimated 52.4% in LSIL, but there was no case overestimated. HSIL group revealed 42.9%, 57.1% in severe dysplasia and CIS respectively. Punch biopsy was revealed accuracy with LEEP in 76.2%, but underestimated in 16.7% and overestimated in 7.1%. HPV DNA were positive in 15.4% of mild dysplasia, 25% in moderate dysplasia and 75%, 88.9% in severe dysplasia and CIS respectively. 11.9% of participants showed positive resection margins after LEEP. All subjects included low abdominal discomfort among their complications. But there was no serious complication. CONCLUSION: LEEP seems to be an effective method of diagnosis and treatment of cervical dysplasia based on cytology and colposcopically directed biopsy.