Objective:To evaluate the efficacy of loop electrosurgical excision procedure(LEEP) in the treatment of different grade of cervical intraepithelial neoplasia(CIN). Methods:898 cases with CIN treated by LEEP were retrospectively analyzed. Operation time, blood loss during the operation, changes of histopathologic results and high-rick HPV before and after the operation were studied. The diagnosis and treatment results by LEEP were evaluated. Results: The average operation time was 5.1 minutes. The average blood loss during the operation was 5.6 ml. The concordance rate of pathologic results under colposcope before operation and after LEEP was 77.73% (698/898) .96 cases had increased CIN grade after LEEP(10.69%). The HPV-DNA loading dose after operation declined significantly (P< 0.01). Conclusions: The detection rate of invasive cervical cancer by LEEP is higher than multiple punch biopsy under electronic colposcope. LEEP is an effective method for the diagnosis and treatment of CIN, and it can eliminate high-rick HPV at the same time of ablating the cervical lesion.