To evaluate the correlation between the serum SCC Ag(Squamous Cell Carcinoma antigen) level and tumor volume measured by MRI(Magnetic Resonance Imaging), we studied 32 patients with invasive cervical carcinoma, 15 patients with cervical intraepithelial neoplasia, and 10 healthy women who were admitted to Ajou University Hospital, Department of Obstetrics and Gynecology from December 1, 1994 to Aug 31, 1995. Serum SCC Ag levels were measured by Microparticle Enzyme Immunoassay technique va IMx SCC assay and tumor volume was measured with 1.5 T Signa System (GE, Milwaukee, WI., USA) by obtaining sagittal and axial views with Fast Spin Echo T2 weighted series and consequently reconstructed to 3 dimension, calculating the mean value. The results obtained as follows: 1. The mean value and positive rate of SCC antigen were higher in invasive cancer(6.0 ng/ml and 50%, respectively) compared with control(0.5ng/ml and 0%, respectively) and cervical intraepithelial neoplasia(1.6ng/ml and 26%, respectively). 2. The mean value of serum SCC antigen level was more elevated in patients with squamous cell carcinoma(5.7ng/ml) than in patients with endocerival adenocarcinoma(1.7ng/ml) and adenosquamous cell carcinoma(1.6ng/ml). This difference was not statistically significant. 3. Serum SCC antigen level was increased according to the increase of tumor volume. This difference was statistically significant. 4. The relationship between serum SCC antigen level and clinical lesion size was not significant statistically. In conclusion, it would be suggested that measurement of pretreatment serum SCC antigen levels and tumor volume by MRI are helpful in pretreatment prognostic factor after treatment.