Patients with type 2 diabetes can eat a small amount of watermelon when their blood sugar control is good, while those with poor blood sugar control are not recommended to eat watermelon. Watermelon has a glycemic index of 73, which is a high glycemic index fruit and is not conducive to blood glucose control, but when blood glucose control is better, a small amount of watermelon can be consumed between meals, and postprandial blood glucose monitoring is recommended. In addition, if the blood sugar control is not good, it is not recommended to eat watermelon, which is not conducive to disease control. Diabetic patients should strictly control their diet, rationalize their diet, eat less and more meals, exercise moderately, and follow the doctor’s instructions for reasonable and standardized medication, so that they can better control their blood glucose. It is recommended to observe the changes of the condition and monitor blood glucose, and consult a doctor if there is any discomfort, so as to avoid delaying the condition.