Diabetes (lat. diabetes mellitus) can be defined as a syndrome characterized by the body's inability to regulate blood glucose levels. Today more people than ever before suffer from it, from adults to children and adolescents. If the blood glucose level rises over the years, it can lead to complications that affect eyes, kidneys, feet, heart, blood vessels and nerves. To avoid this, it is important to monitor blood glucose levels. With proper nutrition, physical activity and medical therapy, the basic principles of diabetes treatment are self-monitoring and patient education. If the patient is a child, education of parents and teacher's knowledge about the health needs of students is important so that they can respond in a timely manner in the event of complications. Eventually, with the help of parents and professionals, the child will learn to take care of their condition. The research aim was to examine the knowledge of primary school teachers and extended-stay teachers about diabetes, to determine their views about the disease and proper education, to examine the experiences of students and see the impact of diabetes on their daily routines and their willingness to help a student with diabetes in certain situations. The research was carried out using a Google survey questionnaire among 265 primary school teachers in the Republic of Croatia. The results of the research showed that teachers have basic information about diabetes and consider it a serious disease that requires their attention during their work. Although they are familiar with terms/vocabulary related to the disease, the research showed a dissatisfaction among the teachers with their own knowledge, but also a willingness of teachers to attend training seminars in order to find out more about the disease and acquire greater competencies in dealing with students with diabetes. Based on the results of this research, it can be concluded that teachers agree that education, support, cooperation and communication with parents are crucial in diabetes management. The research can serve as inspiration for organizing training seminars for teachers in schools.