Epilepsy is a disease of the nervous system. Some cases of epilepsy are resistant to pharmacotherapy. One of the treatment methods is the ketogenic diet, which is characterised by a low carbohydrate content in favour of fats. The aim of the study was to assess the level of knowledge of parents of children with epilepsy regarding the ketogenic diet. Conducted between January and March 2025, the study involved 62 parents of children with epilepsy. Parents of children diagnosed with epilepsy at an early age more frequently demonstrate a knowledge of the main principles of the ketogenic diet. Respondents perceive the ketogenic diet as a form of treatment. Knowledge of the contraindications to the ketogenic diet is limited, and depends primarily on the respondents’ level of education. Respondents are aware of the necessity of implementing the ketogenic diet under the supervision of a physician and a clinical dietitian.