Objective. The main objective of the study is to assess the knowledge of parents/guardians about body posture defects in children at early school age. During the study, additional objectives were set regarding the determination of the level of parents’ knowledge in selected topics. These topics concerned the type of body posture defects in children, factors influencing their formation, as well as determining the knowledge of parents in the use of preventive measures. Material and methods. The study group consisted of 300 parents of children at early school age. The study was conducted on the basis of an original, anonymous questionnaire consisting of 24 questions. Respondents provided answers to questions concerning, among others, the source of obtaining information on posture defects, knowledge of individual posture defects and methods of prevention. Results. The study showed that people living in larger towns/cities and having higher education have a wider range of knowledge in the field of body posture defects. In addition, respondents with higher education know and use posture defect prevention methods much more often than people with lower education. According to the respondents, wearing a backpack on one shoulder is one of the most common causes of posture defects. Parents who do not know whether their child has a posture defect relatively rarely use preventive methods.