Background: World Health Organization (WHO) guidelines recommend that infants should be breastfed for six month after childbirth. The average duration of breastfeeding in Taiwan still falls short of this sixth-month timeline. In order to improve the duration of breastfeeding, it is crucial to understand the factors that affect related behavior. Purpose: To explore the effects of breastfeeding self-efficacy and breastfeeding intention among exclusivebreastfeeding women during the initial six months after childbirth and to verify the reliability and validity of the infant feeding intentions scale (Chinese version). Method: Purposive sampling was used to select and enroll a total of 167 breastfeeding women from a southern metropolitan medical-teaching hospital. Data were collected using a structured questionnaire and phone interviews. Data were analyzed using SPSS 18.0, LISREL8.7, and S-Plus package software to obtain scores for the independentsample t test, Pearson's product-moment correlation coefficient, one-way analysis of variance, survival analysis, and reliability and validity. Results: Breastfeeding self-efficacy scores ranged from 14 to 70, with a mean score of 44.80 (±11.56). Infant feeding intention scores ranged from 14 to 70, with a mean score of 12.20 (±3.14). Additionally, 29.9% of the participants breastfed exclusively for the entire six months after childbirth. Breastfeeding self-efficacy and breastfeeding intention were positively correlated (r = .45, p < .001). Education level, occupation, and breastfeeding intention were each identified as factors that significantly influenced the success of exclusive breastfeeding during the initial six months after childbirth. Conclusions/Implications for Practice: Breastfeeding self-efficacy and breastfeeding intention are correlated with breastfeeding behavior. Based on findings, medical staff should target promotion and education regarding the importance of breastfeeding particularly toward women who have lower levels of education, who are employed, and who express low initial intention to breastfeed.