Watermelon is not recommended for patients with gestational diabetes. Watermelon is rich in vitamin C, vitamin A, vitamin B and other nutrients, but its glycemic index is high, 72, belonging to the high glycemic index of food, gestational diabetes may cause greater fluctuations in blood glucose after eating watermelon, so gestational diabetes patients are not recommended to eat watermelon. Gestational diabetes patients can give priority to some low glycemic index fruits such as apples, cherries, etc., need to pay attention to eat in moderation, so as not to cause significant fluctuations in blood glucose. Patients diagnosed with gestational diabetes mellitus should actively cooperate with the doctor’s treatment, maintain a low-glycemic diet and appropriate exercise to help maintain blood sugar stability.