Abstract: AIM: To compare the features of percutaneous coronary intervention (PCI) between coronary heart disease (CHD) patients complicated with or without diabetes. METHODS: A cohort of 1 441 consecutive CHD patients treated with PCI from January to December 2006 in Tianjin Chest Hospital were analyzed retrospectively. The patients were divided into two groups: CHD with diabetes mellitus group and CHD without diabetes mellitus group. PCI-related data were collected and compared between groups. RESULTS: Two hundred and twenty-three patients (15.5%) were found complicated with diabetes. Type C lesion was more prevalent in patients with diabetes than those without diabetes (38.3% vs. 19.7%; P<0.05). The number of treated lesions and implantation of stents and drug-eluting stents in diabetic group were higher than in the nondiabetic group (1.42±0.62 vs. 1.28±0.51; 1.63±0.84 vs. 1.47±0.69, P<0.05). The average stent diameter was smaller in the diabetic group compared with that in the nondiabetic group ［(3.00±0.42) mm vs.(3.06±0.43) mm, P<0.05］. CONCLUSION: Coronary artery lesions are more serious in CHD patients complicated with diabetes mellitus. Therefore, more lesions are treated and more stents are implanted in patients complicated with diabetes. PCI intervention rate is lower in CHD patients complicated with diabetes compared with that in CHD patients without diabetes.