High blood sugar may cause dizziness. High blood sugar may be caused by physiological factors such as a high-sugar diet, emotional excitement, doing strenuous exercise for a short period of time, or stress factors such as infection, fever, angina, or heart attack; or the patient may be suffering from diabetes themselves. All of these reasons can cause the body’s blood sugar to exceed the normal range. When the body’s blood sugar continues to exceed the normal range, it is easy to lead to an increase in blood viscosity, which will affect the blood circulation in the brain, and when the blood supply to the brain is insufficient, it may cause dizziness. At the same time, diabetic patients with high blood glucose for a long time without control may develop cardiovascular and cerebrovascular diseases, such as cerebral infarction, or autonomic dysfunction and postural hypotension, which can cause dizziness. Therefore, patients with high blood sugar dizziness, it is recommended to go to the hospital to do blood tests, cranial CT and other related examinations, to clarify the specific causes of dizziness, and under the guidance of the doctor’s treatment.