Carotid artery thickening is mainly caused by atherosclerosis caused by the presence of hypertension, hyperlipidemia, diabetes, smoking, alcohol consumption, and staying up late at night, and is part of systemic atherosclerosis. Carotid artery thickening can cause luminal narrowing and the formation of atheromatous plaque shedding, which may also cause cerebral infarction. In addition to thickening of the carotid artery caused by atherosclerosis, thickening may also be caused by arteritis. The thickening caused by arteritis is mainly due to intimal hyperplasia caused by immune factors, viral infection, etc., resulting in luminal narrowing. The specific cause also depends on the condition, and if necessary, relevant examinations should be performed for clarification and targeted treatment.