Abstract: Type 2 diabetes mellitus (T2DM) and geriatric syndromes frequently coexist in older adults. They interact with each other and form a complex vicious cycle, constituting an important contributor to adverse clinical outcomes. Available evidence suggests that T2DM, through multiple mechanisms such as insulin resistance, chronic inflammation, oxidative stress and mitochondrial dysfunction, promotes the onset and progression of a range of geriatric syndromes such as frailty, cognitive impairment, malnutrition, depression and sleep disorders. Conversely, geriatric syndromes, via pathways such as reduced mobility, inadequate nutritional intake and diminished self-management capacity, further exacerbate metabolic dysregulation, thereby accelerating diabetes progression and increasing the risks of falls, disability and death. The two conditions do not merely coexist, they are coupled through a shared pathological basis centered on insulin resistance and form a persistently reinforcing vicious cycle between functional decline and metabolic disturbance. Multidimensional intervention strategies based on comprehensive geriatric assessment facilitate early identification and individualized management, thereby improving patients’ functional status and overall prognosis. Accordingly, this article systematically reviews T2DM complicated with geriatric syndromes from the perspectives of epidemiological characteristics, shared pathophysiological mechanisms, and integrated management strategies, and proposes a shift in management from a “disease-centered” to a “function-centered” model, in which overall functional status, including mobility, self-care ability and cognitive function, is emphasized alongside glycemic control, thereby providing new insights and evidence for optimizing comprehensive management and improving prognosis in elderly patients.