Purpose: This study was conducted to develop a customized birth control program and identify its effects on attitude, subjective norm, behavioral control, intention, and behavior of contraception among immigrant postpartum mothers. Methods: In this experimental study, Vietnamese, Filipino or Cambodian married immigrant postpartum mothers were recruited. They were assigned to the experiment group (n=21) or control group (n=21). The customized birth control program was provided to the experimental group for 4 weeks. Results: The experimental group showed a significant increase in the score of attitude, subjective norm, behavioral control, intention, and behavior of contraception. Conclusion: Findings in this study indicate that the customized postpartum birth control program, a systematic and integrative intervention program composed of customized health education, counseling and telephone monitoring, is able to provide effective planning for postpartum health promotion and birth control behavior practice in married immigrant women.