Objective To investigate the occurrence and risk factors of type 2 diabetes mellitus (T2DM) patient treated with continuous subcutaneous insulin infusion (CSII) hypoglycemia during perioperative period. Methods A total of 96 patients with fractures and T2DM who received CSII therapy during perioperative period in Beijing Jishuitan Hospital were selected as research subjects. Clinical data including medical history, glycosylated hemoglobin (HbA_1c), liver and kidney function, occurrence of hypoglycemia and postoperative complications were collected. Logistic regression analysis was used to analyze the risk factors of hypoglycemia. Results The average time reaching the blood glucose target was (2.8±1.3) d in the perioperative patients with T2DM received intensive CSII treatment, and the overall incidence of hypoglycemia was 15.6%. There were 15 patients in the hypoglycemia group and 81 patients in the non-hypoglycemia group. Compared with the non-hypoglycemia group, the hypoglycemia group was older [(71.1±11.1) years vs (56.0±10.6) years, P=0.000] and had longer course of disease [14.0 (8.8-17.8) years vs 5 (2.8-12.0) years, P=0.017], lower estimated glomerular filtration rate (eGFR) [(78.7±27.5) mL/(min·1.73 m²) vs (106.8±15.0) mL/(min·1.73 m²), P=0.005], and higher incidence of postoperative infection (25% vs 3%, P=0.024). Logistic regression analysis showed that older age (OR=1.172, 95%CI: 1.027-1.091, P=0.012), longer course of disease (OR=1.193, 95%CI: 1.001-1.420, P=0.049) and lower eGFR (OR=0.950, 95%CI: 0.903-0.998, P=0.049) were independent risk factors for hypoglycemia in perioperative T2DM patients treated with CSII. Conclusions The perioperative T2DM patients can quickly achieve the blood glucose target through CSII therapy. Older age, long course of diabetes and low eGFR level are risk factors for hypoglycemia.