Health education is the foundation for the non-pharmacological control of hypertension and diabetes and proposes reflection on the importance of co-responsibility for self-care. This study aimed to analyze the impact of nurses' actions on health education of hypertensive and diabetic patients in a Basic Health Unit. This was a descriptive, interventionist study with a quantitative approach. Most of the participants were female, married, with incomplete elementary school. The most prevalent risk factors were: family history, stress and sedentary lifestyle. There was an increase in understanding about the concepts of diseases, lifestyle habits, importance of non-pharmacological treatment, recognition and prevention of complications, frequency and quality of food and frequency and duration of physical activity. The findings reinforced the importance of the role of nurses as a health educator and as a promoter of changes in life habits, contributing to the control of diseases.