Slowed blood flow in the vertebral artery is a pathologic condition, and possible causes include vertebral artery atherosclerosis, vertebral artery cervical spondylosis, and cardiac insufficiency. 1. Vertebral artery atherosclerosis: the causes of this disease are mostly related to hypertension, diabetes mellitus, hyperlipidemia and so on. If the patient’s blood pressure, blood glucose, blood lipids and other control is not good, it can lead to the formation of vertebral artery atherosclerosis plaque, resulting in the narrowing of the lumen of the blood vessel, causing the slowing down of blood flow. 2. Vertebral artery-type cervical spondylosis: this disease is mainly due to cervical vertebral osteophytes compressing the vertebral artery, which causes slowing of vertebral artery blood flow. 3. Cardiac insufficiency: when suffering from cardiac insufficiency and heart failure, the ejection fraction is significantly reduced, and the blood supply to the brain is reduced, thus affecting the blood flow rate of the vertebral artery. When patients are found to slow down the blood flow of the vertebral artery, it is recommended to go to a regular hospital in time, under the guidance of a specialist physician to improve the relevant examinations, and give targeted treatment to prevent delayed condition.