OBJECTIVE: To evaluation of the effect of pelvic or paraaortic lymphadenectomy on survival rates in the management of clinical stage I endometrial cancer METHODS: A retrospective analysis was performed on a total 303 clinical stage I endometrial cancer patients from 1989 to 2004 at Asan Medical Center. Two hundred-sixty-three (86.8%) underwent a total hysterectomy and bilateral salpingo-oophorectomy with pelvic or paraaortic lymphadenectomy, while forty (13.2%) underwent a total hysterectomy and bilateral salpingo-oophorectomy only. Characteristics of patients and 5-year survival rate of each patients group were analyzed. RESULTS: Seventeen (6.5%) showed lymph node metastases and overall 5-year survival rate of clinical stage I endometrial cancer was 96.9%. The 5-year and 10-year survival rate of a group with lymphadenectomy were 96.4% and 86.6%, and those of a group without lymphadenectomy were 100% and 75.2%, respectively (p=0.48). The 5-year survival rate of a group with positive lymph nodes was 73.3%, that of a group with negative lymph nodes was 97.7% (p<0.05). CONCLUSION: The complete staging operation including lymphadenectomy did not improve the survival rates in a group with lymphadenectomy significantly. But the debates regarding the necessarity of lymphadenectomy in clinical stage I endometrial cancer still remains and a large randomized prospective study is needed.