Aim To study the effects of diabetes and balloon injury on diet induced arterial atherosclerosis in rabbit. Methods Set up rabbit atherosclerotic model by high cholesterol diet and injury of abdomen aorta's endothelium with balloon;half of the animals were injected alloxan one week before endothelium injury to make diabetic atherosclerotic model,atherosclerotic rabbits were injected physiological saline instead.Ten weeks after the surgery rabbits were sacrificed by euthanasia,transverse sections of the aorta were taken for H&E stain and immunohistochemistry to analyze intima incrassaition,quantities of macrophages and smooth muscle cells. Results Thoracic and abdomen aorta of both diabetic and non-diabetic rabbits developed atherosclerosis,and the ratio of intima to media thickness in thoracic aorta(0.9±0.18 and 0.7±0.2 repectively) was much lower than in abdomen aorta(6.9±2.0 and 6.9±2.1 repectively).Though intima thickness of the abdomen aorta was similar between the two groups,diabetic atherosclerotic rabbits had more macrophages(percentage of positive stain area in the intima was 39.7±8.7) and fewer smooth muscle cells(percentage of positive stain area in the intima was 29.6±5.5) in its intima than non-diabetic atherosclerotic rabbits(percentage of positive stain area of macrophages were 38.7±5.8 and that of smooth muscle cells were 35.2±4.9),especially at luminal 1/2 of intima(percentage of positive stain area of macrophages were 18.8±4.8 and 33.9±6.2 respectively and that of smooth muscle cells were 32.8±5.8,25.4±3.8 respectively). Conclusion Balloon injury of the endothelium accelerates atherosclerosis induced by diet in diabetic and non-diabetic rabbits;diabetes promotes inflammation of the atherosclerosis.