The promotion of healthy infant feeding is increasingly recognized as an important obesity-prevention strategy. This is relevant for American Indian populations that exhibit high levels of obesity and low compliance with infant feeding guidelines. The literature examining the knowledge, attitudes, and beliefs surrounding infant feeding within the American Indian population is sparse and focuses primarily on breastfeeding, with limited information on the introduction of solid foods and related practices that can be important in an obesity-prevention context. This research presents descriptive findings from a baseline knowledge, attitudes, and beliefs questionnaire on infant feeding and related behaviors administered to mothers (n=438) from five Northwest American Indian tribes that participated in the Prevention of Toddler Overweight and Teeth Health Study (PTOTS). Enrollment occurred during pregnancy or up to 6 months postpartum. The knowledge, attitudes, and beliefs questionnaire focused on themes of breastfeeding/formula feeding and introducing solid foods, with supplemental questions on physical activity. Knowledge questions were multiple choice or true/false. Attitudes and beliefs were assessed on Likert scales. Descriptive statistics included frequencies and percents and means and standard deviations. Most women knew basic breastfeeding recommendations and facts, but fewer recognized the broader health benefits of breastfeeding (eg, reducing diabetes risk) or knew when to introduce solid foods. Women believed breastfeeding to be healthy and perceived their social networks to agree. Attitudes and beliefs about formula feeding and social support were more ambivalent. This work suggests opportunities to increase the perceived value of breastfeeding to include broader health benefits, increase knowledge about solid foods, and strengthen social support.