There is no season when diabetes is most likely to strike, but blood sugar may fluctuate more during the winter months when temperatures are cooler. Patients with diabetes are particularly susceptible to cold weather and have lower blood glucose stability during the winter months. In winter, when temperatures are cooler, normal body temperature is maintained by skeletal muscle contraction to increase heat production or vasoconstriction to decrease heat loss. Diabetic patients have poorer ability to control vasoconstriction, impaired thermoregulatory mechanisms and autonomic nervous system responses, which may result in lower body temperature, lower glycemic control, and poorer glycemic stability, leading to more frequent fluctuations in blood glucose in winter. It is recommended that diabetic patients keep warm in winter, standardize their diet, take medication according to doctor’s instructions, apply insulin regularly, measure blood glucose on time, and once frequent fluctuation of blood glucose occurs, it is recommended to go to the hospital as soon as possible, and adjust the treatment plan under the guidance of the doctor.