Recently, the rate of cesarean section in Korea has been increasing. The results of several previous studies in foreign countries on the emotional responses of cesarean section mothers showed that they might experience difficulties in the mother-infant interaction due to fatigue, lack of early mother-infant interaction, disappointments, anger, feelings of loss of control, and other factors. Human behavior is said to be determined by one's self concept, and self concept is influenced by both internal and external environmental factors. A scale to measure the self concept of cesarean section mothers was needed in order to identify those who might have difficulties in the mother-infant interactions in future. The purpose of this study were to develop a measuring scale, and to test its reliability and validity. The process of this study was as follows. A structured interview was done with 50 cesarean section and vaginal delivery mothers to fine their state of emotional reaction after giving birth to their babies. Based on the results of the interviews, a 50 items Likert scale was developed. The self concept of 268 cesarean section and vaginal delivery mothers who were hospitalized at six hospital in seoul were measured, during the period between Feb. 1 and April 30. Reviewing the discriminating power of each item by means of crosstabulation, ten items were selected for the final scale. The reliability and validity of this ten item scale were tested by Cronbach's alpha and t-test, using spss pc+package. The results of this study and recommendation are as follows. 1. The ten selected items were as follows. I feel pains in my breast.(-) I have a good appetite now.(+) I feel pains in my flank.(-) I feel fine now.(+) My body seems to have returned to its prepregnant state.(+) Thinking of the delivery process, I feel sorry.(-) I want to hold my baby in my arms.(+) I want to keep my own life, even if I became a mother. (-) I want to delegate the care of the baby to my mother/mother in law.(-) I think baby is my alter ege.(+) 2. The reliability of this scale was tested by Cronbach's alpha, and the coefficient of this scale was 0.8066. 3. The construct validity of this scale was tested by means of known group methods. The value of self concept for cesarean section mother was significantly lower than for vaginal delivery mothers(t=-5.51, df=226, p=0.007). 4. The criterion validity of this scale was tested indirectly. Though this scale could discriminate the section and vaginal delivery mothers, the five items on the personal self concept scale didn't show any difference between cesarean section and vaginal delivery mothers. Therefore, the study indicate that those who shows lower values in the personal self concept measurement, that is, lower than 12.03 points, could be regard as "risk mothers". 5. Further studies using this scale to clarify the influencing factors on negative self concept are strongly recommended.