Aim To investigate the effect of curcumin on the expression of matrix matalloproteinase-9 in the aorta atherosclerotic rabbits. Methods Thirty male Japanese White rabbits were fed with high-cholesterol diet for two consecutive months. After atherosclerotic model was established, the remaining animals were randomly divided into two groups: the control group and treatment group. Both groups were fed with standard diet for next one month. Additionally, the treatment group received an oral curcumin at dose 200 mg/kg, and the control group received an oral curcumin-free sodium chloride solution daily during experiment. Before and after the curcumin therapy period, the blood sample were collected in both groups. Serum was separated and used for the assessment of total cholesterol, low density lipoprotein cholesterol (LDLC), high density lipoprotein cholesterol (HDLC) and triglyceride. After three months, all animals were killed. Entire aortas were rapidly dissected out, and the ratio of atherosclerotic plaque was examined. The aortic arch was selected for histological examinations and stained with hematoxylin and eosin (H & E). The expression of MMP-9 was examined with semiquantitative analysis immunohistochemistry in the aorta. Results Both treatment and control group had eight rabbits for analysis. After curcumin treatment for one month, compared with the control group, the treatment group decreased serum triglyceride by 23.5% (0.75±0.15 mmol/L vs 0.98±0.20 mmol/L, P=0.024), total cholesterol by 21.6% (3.52±0.66 mmol/L vs 4.49±0.80 mmol/L,P=0.020) and LDLC by 30.3% (2.05±0.43 mmol/L vs 2.94±0.72 mmol/L,P=0.009), but increased HDLC by 16.3% (1.14±0.15 mmol/L vs 0.98±0.14 mmol/L,P=0.040). Curcumin inhibited the atherosclerotic development in experimental rabbits, the ratio of plaque with area reduced obviously in treatment group as compared to those of control group (22.61%±7.95% vs 42.28%±19.34%,P=0.025). The stained intensity, ratio of positive cell and total score of MMP-9 immunohistochemistry expression were significantly lower in treatment group than those in control group. Conclusion Curcumin could decrease the expression of matrix metalloproteinase-9 in the aorta and attenuate atherosclerotic development in rabbits.