Between Mareh 1, 1990, and February 29, 2992, 188 CO laser conization were performed. All women enrollert in this study had cervical cytology, colposcopy, and colposeopicaJly directed biopsies. Indications of laser conization were that directed biopsy specimen was proved CIN 3 or suggests possible stromal invasion. In all of the cases the proeedures were carried out with the patients under local anes-thesia. The laser power is turned up to 23 W and the spot size is reduced to 0,5aw in diameter. The height of cone specirnen was 1.5 to 2cm. The cone apex is cut with a sharp sealpel. Excisional cone sections(2,256) were evaluated for lesion length, depth and clear margin, A patient was considered cured of disease when the Papanicolaou smear and colposcopic examination were normal for a period of l year or more. Of the 188 women with managed by laser conization, 96(51.1%) were aged 39 or less and 6(3.2%) were nulliparous. Of the 129 women wi.th diagnosed ClN 3 on a colposcopically directed biopsy, 29(22.5%) were microinvasive carcinoma and 2(1.6%) were invasive carcinoma of the cervix. 17(9.0%) women had the diagnosis of invasive carcinoma made on eomxation in the absence of any cytological, colpoacopical or directed puneb biopsy forewarning of invasive carcinoma. CIN 3, 135(91.8%) wmen who had a laser conization showing negative margin, 135(100%) had no evidence of persistent or recurrent disease during follow-up examination. The 12(8.2%) women who had positive marging were performed hystereetomy. 3(1,6%) women had bleeding that required transfusion. One case of pelvic infection and one case of ceruical stenoais were observed, The laser excisional cone provides a large and exeellent specimen for the pathologist to review because the diameter of burned tissue was 0, 2mm. This study demorisirated that CO2 laser conization was a highly effective method for treating high grade cervieal intraepithelial neoplaaia and wMed benefit of preserving reproductive function and rule out invasive carcinoma.