Objectives: To evaluate the effects of a well-designed, maternity-oriented antenatal education program (Korean Gentle Birth, KGB) that introduced from the Leboyer Birth and modified in Korea. Methods: Subjects were over 16 weeks primipara pregnant women who visited an obstetric hospital (one of the current six membership health organization of KGB in Korea) in Kimhae city for antenatal care and informed consented to join in this study; the total 182, 89 with KGB (case) and 93 with only general antenatal care without KGB (control). They were collected during four terms of the KGB from August 2010 to March 2011. Value of maternity, cognition to antenatal education, attitudes to labor, interests and cooperations of the spouse, executing mother-infant attachment and the desirable maternal performance after delivery were surveyed with direct interview using questionnaire. Data analysis was performed using MedCalc (ver 11.5, Mariakerke, Belgium). Level of each categories' responses were presented and compared as the score out of 100. The rate and mean compared by chi-square test, t-test, and paired t-test. And, multiple logistic regression (MLR) analysis conducted on the over five times use of 'room in one' and the over one year's intention of breast feeding. p<0.05 was considered statistically significant. Results: There were no differences in age, education, income, whether planned pregnancy, and-Young-Ran Kim, et al.: Improvements of Behavior and Attitude of Pregnant Women Trained by A Maternity-oriented Antenatal Education Program: Assessment of Korean Gentle Birth (KGB) Program