Postprandial blood sugar of 6.3 mmol/L is normal. The composition of postprandial blood glucose mainly includes two factors: one is the energy intake in the food after eating, which leads to the increase of blood glucose level in the body; the other part is the increase of blood glucose will cause the corresponding increase of insulin secretion in the body to lower the sugar, and then the increased blood glucose will fall back. The two factors of sugar increase and sugar decrease in the body are kept in dynamic balance, thus maintaining the blood sugar level in the body within a small range of fluctuation. Most people’s postprandial blood glucose does not exceed 7.8 mmol/L. If postprandial blood glucose reaches or exceeds 11.1 mmol/L continuously, it is likely to be a sign of diabetes. And for pregnant women who underwent glucose tolerance test at 24 weeks of gestation, if the two-hour blood sugar is ≥8.5mmol/L, it is abnormal. Therefore, a postprandial blood glucose of 6.3 mmol/L is normal for the entire population.