Background: Diabetes is a fast-growing health problem in Egypt with a significant impact on morbidity, mortality, and health care resources. Health promoting behaviors is positively associated with diabetic control among elderly diabetics; this study indicated that practicing health-promoting behaviors led to better control of diabetes. The aim of this study was to evaluate the effect of health promoting behaviors intervention on elderly diabetics at Abu Kabir central hospital. Research design: A quasi-experimental design was used to conduct this study. Setting: The study was conducted at Abu Kabir central hospital's outpatient internal clinic.Subject: This study included 60 elderly patients and older. Tools: Tool I: A Structured Interview Questionnaire which consisted of three parts; part 1; demographic characteristics, part 2; Previous and current medical history of elderly diabeticsm and Part3; Concerned with Diabetes mellitus knowledge Tool II: Rating scale which includes two parts; part 1; parts. Health promotion life styles profile II (HPLP) factors II, and part 2; A-predisposing factors to promote health behaviors of elderly diabetics. Results: It was found that there was a highly significant (p<0.001) relation between total scores of behaviors and knowledge of elderly diabetics. Conclusion: The applied training program is effective in improving studied elderly diabetics knowledge, health-promoting behaviors regarding diabetes mellitus. Recommendation: The developed Health-promoting behaviors training program should be applied in diabetic clinics, family care units and geriatric home care to better control of diabetes mellitus, which lead to eliminate complications among elderly diabetics.