Objective To investigate the relationship between the prolonged QTc interval and the multi-cardiovascular risk factors in patients with type 2 diabetes mellitus(T2DM). Methods Medical data of 3940 T2DM patients were analyzed. After patients who had coronary heart diseases, arrhythmia, myocardial infarction, which may cause abnormal QTc, were excluded, a total of 3426 T2DM patients who had underwent diabetic complication assessment and 12 standard electrocardiogram(ECG) recording were enrolled. They were divided into normal QTc interval group(QTc＜0.44 s, n = 2157) and prolonged QTc interval group(QTc≥0.44s, n = 1269). The multi-cardiovascular risk factors were compared between the two groups and further analyzed. Results Compared with normal QTc interval group, the patients in prolonged QTc interval group were older[(55.6±11.0) vs (54.6±10.9) years], had longer diabetes duration[36(12, 96) vs 36(6, 84)months, median(P25, P75)], more females (51.5% vs 41.5%), shorter body height[ (1.64±0.08) vs (1.65±0.08) m], bigger body mass index(BMI)[(26.2±3.6) vs (25.8±3.2) kg/m2], bigger waist circumference[(89.7±9.6) vs (88.2±9.5) cm], bigger hip circumference[(95.4±7.3) vs (94.4±6.6)cm], higher waist hip ratio(WHR)[(0.94±0.07) vs (0.93±0.08)], higher blood pressure [(134.8±20.3) /(76.9±10.2) vs (130.1±19.1) /(74.5±9.6) mmHg], increased heart rate [(82.9±10.2) vs (70.7±10.1)beats/min], higher HbA1c [(8.0±2.0)% vs (7.7±1.9)%], higher post-meal glucose[(13.7±5.1) vs (12.8±4.8) mmol/L], higher fasting insulin[(9.4±8.6) vs (8.2±7.5)IU/ml], increased total cholesterol[(5.1±1.1) vs (5.0±1.1) mmol/L], higher triglyceride [(2.4±2.6) vs (2.2±2.5) mmol/L], and higher urine albumin/creatinine(Alb/Cr)[15(8, 36) vs 12 (7, 27) mg/g, median(P25, P75)]. All these indices were significantly different between the two groups(P＜0.05). Logistic regression analysis showed that factors including age, sex, BMI, waist circumference, WHR, heart rate and Cr, were significantly associated with prolonged QTc interval. Conclusions More than one third of T2DM patients present with prolonged QTc interval and more severe multi-cardiovascular risk factors.