The population of older adults with diabetes mellitus is growing but heterogeneous. Because geriatric syndromes, comorbidity or multimorbidity, the complexity of glucose dynamics, and socioeconomic conditions are associated with the risk of severe hypoglycemia and mortality, these factors should be considered in individualized diabetes treatment. Because cognitive impairment and frailty have similar etiologies and risk factors, a common strategy can be implemented to address them through optimal glycemic control, management of vascular risk factors, diet, exercise, social participation, and support. To prevent frailty or sarcopenia, optimal energy intake, adequate protein and vitamin intake, and resistance or multi-component exercise are recommended. For hypoglycemic drug therapy, it is important to reduce hypoglycemia, to use sodium glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists, taking into account the benefits for cardiovascular disease and the risk of adverse effects, and to simplify treatment to address poor adherence. Glycemic control goals for older adults with diabetes should be set according to three categories, based on cognitive function and activities of daily living, using the Dementia Assessment Sheet for Community-based Integrated Care System 8-items. This categorization can be used to determine treatment strategies for diabetes when combined with the Comprehensive Geriatric Assessment (CGA). Based on the CGA, frailty prevention, treatment simplification, and social participation or services should be implemented for patients in Category II and above. Measures against hypoglycemia and for the prevention of cardiovascular disease and chronic kidney disease should also be promoted. Treatment based on categorization and CGA by multidisciplinary professionals would be an individualized treatment for older adults with diabetes. Geriatr Gerontol Int 2024; ••: ••-••.