OBJECTIVES: Exclusive breastfeeding is recommended until the child is six months of age. However, there are many myths about breastfeeding. The aim of our study was to assess the knowledge of Polish women about breastfeeding. MATERIAL AND METHODS: A cross-sectional survey study was conducted among 1536 Polish women. A self-administered questionnaire was created using Google Forms survey management software and distributed online. The participants were asked about the most common myths in society regarding breastfeeding. RESULTS: The highest number of correct answers in all age groups were given to questions related to the nutritional value of breast milk (80.9-94.9%). The fewest correct answers in each age group were recorded to questions concerning the possibility of getting pregnant during the first 6 months of breastfeeding (16.1-35.3%), the safety of drinking non-alcoholic beer during lactation (24.4-37.1%), the benefits of brushing the breast while breastfeeding (16.0-37.1%), and the effectiveness of compresses made of cabbage leaves or sage infusions in relieving ailments during milk rush (6.8-12.4%). Higher education and being a mother were associated with a higher number of correct answers. Age below 25 years was associated with lower number of correct answers. CONCLUSIONS: The results of the survey regarding breastfeeding suggest the existence of various beliefs in the population of Polish women which are not evidence based. This indicates the need for spreading adequate information about breastfeeding, especially among younger women and those who did not obtain higher education.