Coronary atherosclerosis is a chronic inflammatory disease that affects the structure and function of coronary arteries, leading to a series of cardiovascular events. In recent years, the study on the pathogenesis of atherosclerosis in the adventitia of coronary arteries has attracted more and more attention. The adventitia is made up of fibroblasts, progenitor cells, immune cells, microvessels and adrenergic nerves, which surround perivascular adipose tissue. All kinds of tissues and cells of the adventitia have high metabolic activity, which can regulate the structure and function of the whole vascular wall “from the outside to the inside” and participate in the formation of atherosclerosis. This paper reviews the recent advances in the pathogenesis of coronary atherosclerosis in the adventitia of arteries.