Dizziness is possible with postprandial blood sugar 13mmol/L. In normal people, postprandial blood glucose should be less than 7.8mmol/L, while the diagnostic standard for diabetes is greater than or equal to 11.1mmol/L, so postprandial blood glucose 13mmol/L is a more serious situation that requires attention. When blood glucose exceeds the normal range, the elevation of blood glucose is likely to lead to dizziness and other situations. Dizziness caused by high blood sugar may be accompanied by a variety of reasons, which must be analyzed and judged according to the specific situation, and then carry out symptomatic treatment. The cause of dizziness may also be related to blood pressure, insufficient blood supply to the brain, anemia and cervical spine, etc. It is recommended to go to the hospital for comprehensive diagnosis and treatment. Patients with abnormal blood sugar are recommended to go to the hospital in time and receive standardized treatment under the guidance of the doctor.