Functional capacity represents an important indicator of the health condition of the individual with diabetes mellitus, especially in the elderly Aim: This study aimed to assess functional status among elderly patients with diabetes Methods: A descriptive design used to accomplish this study, carried on 200 diabetic patients at outpatient clinic and diabetic unit At Al-Ahrar Educational Hospital at Zagazig City in Sharkia Governorate. Researcher used a structured interview questionnaire included demographic data, medical history, knowledge, and attitude scale for data collection. Results: mean score of transportation functional ability was the highest between all functional ability categories .98 ± .14 while the mean score of laundry functional ability was the lowest .41 ± .49. Additionally, the table explains that the total mean score for elderly women functional ability was 7.02 ± 1.52 and the total mean score for elderly men functional ability was 4.71 ± .66. multivariate analysis identified that female gender and income was statistically significant independent positive predictors of functional ability score. Conversely, age, diseases number, diagnosis history of DM, and sleep score were negative predictors. Conclusion: most of the studied elderly were independent in responsibility for own medication, transportation, using telephone, shopping, and handling finances. More than half of the elderly women were having high functional ability, while more than three quarters of the elderly men were having high functional ability. Recommendation: Development of comprehensive simple Arabic printed educational materials such as pamphlets, books for increasing knowledge of the elderly patients about diabetes. Designing awareness programs and counseling sessions for diabetic elderly aimed at updating their knowledge and guiding them to better control of diabetes mellitus.