Background: Diabetes is a serious chronic disease. Uncontrolled diabetes and poor diabetic patients' knowledge can lead to a high morbidity and mortality. The aim of this study was to assess the effectiveness of structured teaching program on improvement of diabetic patient's health information, treatment adherence and glycemic control. Method: A quasi-experimental research design (pre posttest) was utilized on 72 diabetic patients at Minia University and general hospitals. A Structured Interview questionnaire about diabetic knowledge and treatment adherence. Glucose monitoring parameter (Glycated Hemoglobin & Random Blood Sugar),was monitored. Results: There was a highly a significant improvement in diabetic patients knowledge, treatment adherence and glycemic control post 1 st and 2 nd follow than pre application of teaching program. Conclusion: The diabetic teaching program would improve patient's knowledge about disease, treatment adherence and glycemic control. Recommendations: Nurses should emphasis to provide an teaching program tailored to each diabetic patient and increase their awareness about the importance of diabetic education to improve glycemic control.