Abstract: The concept that atherosclerosis (AS) is a chronic inflammatory disease of the arterial wall has been widely accepted and the immune system has been reported to play an important role in AS occurrence and progression. New research shows that Treg cells can inhibit inflammation in AS, downregulate the inflammation responses and slow the progression of AS. This paper reviews the recent literatures on the relationship between AS and Treg cells, explores the important role of Treg cells in AS occurrence and progression, illustrates the effect of CD3 on the proliferation of Treg cells and its relationship with AS and recommends the new target in the treatment of AS immunology.