OBJECTIVES: The aim of this research is to determine the socio-demographic characteristics of people suffering from high blood pressure, to research their eating and living habits as well as their nutrition knowledge and afterwards to explore whether there is a connection between the level of knowledge about nutrition and their eating habits. STUDY DESIGN: Cross-sectional study PARTICIPANTS AND METHODS: The research was conducted from 7. May 2019. until 28. June 2019. among adults of both genders (18 years of age and more) who were suffering from high blood pressure in the area of Požega-Slavonia County treated in the Medical Centre of the Požega-Slavonia County. There were 400 people with arterial hypertension included in the research in that period. The research was conducted through an anonymous questionnaire which was filled in by subjects. RESULTS: The conducted survey showed deficiencies in the nutrition knowledge, which can be connected to eating habits of participants that were not according to guidelines for treating the disease. The research also proved the connection between the level of nutrition knowledge and eating habits of those suffering from high blood pressure. The extremely negative characteristic in excessive usage of table salt was visible. CONCLUSION: Arterial hypertension is a leading public health issue globally, as well as in Croatia, regardless of accessible awareness of possibilities for prevention of bad eating habits. The assertion that it is necessary to apply more intensive measures of primary prevention, which includes adequate public health strategies and continuous education, is confirmed by this average research.