Previous studies demonstrated that some immunosuppressive agents inhibit arterial intimal hyperplasia. Our previous studies demonstrated that gangliosides (Gang) have an immunosuppressive effect on as well as an anti-inflammatory role in the wound-healing process. Therefore, we decided to examine the effect of Gang on intimal hyperplasia. Twenty Wistar isogenic rats received a transverse division of the anterior wall of the femoral artery, followed by suturing using mononylon 10-0 under surgical microscopy and were then divided into two groups: Gang group, 3 mg/kg per day of Gang, and control group, vehicle, intramuscularly from surgery to death (1 and 3 weeks, respectively). Concentric intimal hyperplasia was observed in arteries stained by hematoxylin-eosin in control and Gang groups. However, the media layer did not demonstrate any major alterations. After 3 weeks, the Gang group showed more intimal hyperplasia than the control group. Therefore, because intimal hyperplasia worsened in the presence of Gang after 3 weeks, further studies will be necessary to clarify its role in intimal proliferation.