Blood glucose 18mmol / L should be timely to the hospital to assess whether diabetes, whether the acute complications of diabetes, and under the guidance of endocrinologists treatment. Normal fasting blood glucose is less than 6.1mmol/L, and 2-hour postprandial blood glucose is less than 7.8mmol/L. Therefore, blood glucose of 18mmol/L, both fasting blood glucose and 2-hour postprandial blood glucose, are obviously elevated. At this time, you should consult a doctor in time to clarify whether diabetes has occurred, whether there are acute complications, such as diabetic ketosis, ketoacidosis. If the diagnosis of diabetes mellitus, should control the diet, moderate exercise, and under the guidance of a medical professional to choose a sugar-lowering program. If combined with acute complications, the complications should be treated promptly, such as correcting ketosis, lowering glucose, and rehydrating fluids. In daily life, blood glucose should be monitored regularly and chronic complications should be screened regularly. Patients are advised to visit the endocrinology department in time.