To evaluate the efficacy and diagnostic and prognostic significance of two tumor markers (SCCA, CA 125) in patient with squamous cell carcinoma of uterine cervix, the authors studied 215 patients with squamous cell carcinoma in situ and invasive carcinoma from September 1993 to November 1996. Both tumor markers were measured coincidently in 215 patients preopera-tively and in 70 cases of benign gynecologic disease for control group. Serum SCCA level of 2.5 ng/ml and CA 125 level of 35.0 U/ml were determined as cut-off levels. The results were as follows: 1. The pretreatment positive rate of SCCA in patient group were 35.8 %(77/215) and 5.7 %(4/70) in control group. 2. The mean values and positive rates of SCCA according to clinical stage were 1.44+/-3.59 ng/ml(8.7 %) for stage 0, 3.81+/-10.22 ng/ml(23 %) for stage I, 8.54+/-15.23 ng/ml(51.3 %) for stage II, 35.54+/-38.34 ng/ml(70.0 %) for stage III, 22.49+/-36.06 ng/ml(75.0 %) for stage IV, 40.33+/-58.66 ng/ml(66.7 %) for recurrent cancer, respectively. The mean SCCA value and positive rate were significantly increased stepwise by clinical stage from stage I to stage III (P<0.05). 3. The pretreatment positive rate of CA 125 in patient group were 21.9 %(47/215) and 17.1 %(12/70) in contrl group. 4. In pre-invasive and invasive groups, the mean value and positive rate of SCCA were 1.44+/-3.59 ng/ml(8.7 %), 9.05+/-25.26 ng/ml(43.2 %), respectively, and it was statistically significant between two groups (P<0.05). The mean values and positive rate of CA 125 were 24.36+/-16.14 U/ml(10.9 %), 35.15+/-59.52 U/ml(24.9 %), respectively, it was not statistically significant (P>0.05). 5. The result of preoperative serum levels of SCCA can be characterized by 35.8 % sensitivity, 94.3 % specificity, 95.1 % positive predictive value, 32.4 % negative predictive value, 49.5 % diagnostic efficiency, and with 21.9 %, 82.8 %, 79.7 %, 25.7 %, 36.8 % respectively for CA 125. Between these two tumor markers, the result of SCCA was more valuable than the other in sensitivity, positive predictive value, negative predictive value and diagnostic efficiency. The results indicate that measurement of SCCA and/or CA 125, have little efficacy in the early detection of squamous cell carcinoma considering it's low rate of positivity in preinvasive and early stage of invasive squamous cell carcinoma. However, in patients with advanced stage invasive carcinoma, measurement of serum SCCA is useful in prediction of prognosis and in early detection of recurrence, and concomitant measurements of SCCA and CA 125 may be more useful in determining prognosis, therapeutic response, and early detection of recurrence than measurement of SCCA alone.