To analyze the predictive value of homocysteine (Hcy) combined with the Framingham risk score for cardio- and cerebrovascular disease in elderly patients with type 2 diabetes mellitus (T2DM) to provide a reference for clinical treatment. We retrospectively reviewed the clinical data of 1036 elderly patients with T2DM admitted to our hospital between July 2017 and July 2022. The patients were divided into occurrence (n = 438) and control (n = 598) groups based on the incidence of cardio- or cerebrovascular disease. Univariate and multivariate logistic analyses were used to analyze the factors associated with cardio-cerebral small-vessel disease in the elderly patients with T2DM. The predictive value of Hcy combined with the Framingham score for cardio- and cerebrovascular diseases in elderly patients with T2DM was determined using receiver operating characteristic curves. Univariate analysis showed that the occurrence group had significantly higher Framingham score, systolic blood pressure (SBP), total cholesterol (TC), fasting blood glucose (FBG), 2-hour postprandial plasma glucose, Hcy, glycated hemoglobin, smoking history, and disease duration than the control group (all P < .05). Food preferences, sleep duration, physical exercise, high density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol levels were significantly lower in the occurrence group than in the control group (all P < .05). Multivariate logistic analysis showed that smoking history, duration of diabetes, Framingham score, SBP, TC, FBG, HDL-C, 2h postprandial plasma glucose, and Hcy levels were risk factors for cardio- and cerebrovascular disease in elderly patients with T2DM. The area under the curve for Hcy and Framingham scores was 0.741 (95% confidence interval [CI]: 0.635–1.871) and 0.717 (95% CI: 0.601–0.856), respectively. Hcy combined with the Framingham score demonstrated a significantly higher predictive value (0.852, 95% CI: 0.741–0.979). Long smoking history, long diabetes duration, high Framingham score, high SBP, high TC, high FBG, low HDL-C, and high Hcy levels are risk factors for cardio-cerebrovascular disease in elderly patients with T2DM. In addition, Hcy level combined with the Framingham score demonstrated superior predictive power for cardio- and cerebrovascular disease in elderly patients with T2DM.