The purpose of this study was to investigate parents' knowledge about diet and dental caries. The survey was conducted using a structured questionnaire consisting of 19 questions regarding knowledge of diet and caries, and preventive measures. The questionnaires were distributed to parents who were visiting a dental hygienist or prophylaxis nurse with their children aged 0-3 years. A total of 88 completed surveys were collected. The study showed that the majority of the parents had knowledge about diet and dental caries. They had good knowledge about snacking, poor oral hygiene and that diet and feeding contents of the bottle can cause tooth decay. Parents have an important responsibility to guide the child to achieve a good general oral health. Thus, dental professionals, especially dental hygienists, have an important role in preventing tooth decay.