The purpose of this study was to investigate the relationship between sex role identity and adaptation to motherhood in normal primiparous women. The sample was composed of 150 primiparous women who attended at prenatal clinic Maharajnakornchiangmai hospital. The researcher interviewed demographic data of the subject, then each subject was requested to complete the Sex Rcle Identity scale and the Adaptation to Motherhood scale. Data were analyzed by using means, standard deviation, one way analysis of variance, Scheffe test, t-test, and Pearson product-moment correlation coefficient to test three hypotheses. The reults were as follows: 1. There were significant differences of adaptatiion to motherhood score among four groups at the .001 level. That is adaptation to motherhood score of the androgynaus and feminine primiparous women were significantly more than those of the undifferentiated primiparous women at the .01 and .05 level accordingly, however, there were no significant differences between other groups. 2. There was a positive relationship between femininity score and adaptation to motherhook score at the .001 level (r = 0.3225). 3. There was a positive relationship between masculinity score and adaptation to motherhook score at the .001 level (r = 0.2665). Furthermore, it was found that there were significant differences of adaptation to motherhood among primiparous women who had different ages, experince to childrearing and planning for this pregnancy at the .05 level.