Background: Their knowledge of preventive health, coupled with their dynamic roles in the community, puts public health professionals in a key position to expand their roles in the health promotion and support of breastfeeding as optimal infant feeding. This online tutorial was created to increase public health professionals’ knowledge about breastfeeding and to assess their attitudes in supporting healthy behaviors related to infant feeding as a health promotion strategy. Method: The study utilized an online breastfeeding tutorial based on the US Breast-feeding Committee recommendations for minimum breastfeeding knowledge for health professionals. Pre- and post-tutorial questionnaires assessed breastfeeding knowledge, and an attitudinal survey evaluated attitudes of public health professionals after the tutorial. Exposing public health students to this information can facilitate the early shaping of their attitudes and understanding about the importance of breastfeeding. Results: Fifty-two Northeastern University MPH students and alumni (62% response rate) completed the study. There was an overall gain in participants’ fundamental knowledge regarding breastfeeding as assessed by pre- (77%) to post-tutorial (97%) correct responses (p = 0.00001). The post-tutorial attitudinal survey showed that 92% of participants were comfortable in answering questions about breastfeeding as part of their professional responsibilities. Conclusion: This pilot study highlights the important role that a short online tutorial can play in expanding public health professionals’ knowledge about breastfeeding. Greater use of online methods can enhance awareness of critical health behaviors, such as breastfeeding, that have not received adequate attention in public health curricula. This pilot study provides the foundation for a larger study. Integration of breastfeeding into public health professionals’ core training could support broader social change.