There are three types of diabetic macules, the most common one being spontaneous, tense blisters, single or multiple, several millimeters to several centimeters in diameter, without surrounding erythema, without pain or itching, self-healing in 2 to 5 weeks, easily recurring, and generally without scarring after healing. The blisters are usually found on the distal extremities, especially on the feet and lower legs. Type 2 blisters heal with scarring and mild atrophy, occasionally with hemorrhagic blisters. The third type is a non-scarring painful blister. Histopathology shows subepidermal blisters, which may be located within the epidermis due to epidermal hyperplasia, with no epidermal echinodermis relaxation. Diabetic maculopathy has the above specific clinical manifestations and is not difficult to diagnose, but still needs to be differentiated from the following diseases: ① Herpetiform aspergillosis: This disease is mostly seen in elderly people over 60 years of age, with widespread lesions, mostly on the chest, abdomen, axillae and flexors of the extremities, as blisters and macules with tense walls, accompanied by varying degrees of itching. The histopathological manifestations are subepidermal blisters and eosinophil-based inflammatory cell infiltration in the dermis. Immunopathology is epidermal basement membrane with linear deposits of IgG and C3; ② herpetic drug rash: a clear history of drug use and a detailed medical history can help in the diagnosis. Fixed drug rash occurs at the junction of skin and mucous membranes, with redness around the blisters, accompanied by pruritus; herpetic epidermal necrolysis-relaxing drug rash is a flaccid blister with positive Ney’s sign and heavy systemic symptoms. (3) Delayed cutaneous porphyria: with photosensitive rash, mostly on exposed areas, with self-induced pruritus or burning sensation. Patients have increased urine porphyrins. ④Papular urticaria: allergic reaction caused by arthropod bites, mostly seen in summer and autumn. It occurs on the extremities and trunk, and is a slightly fusiform red lesion of mung bean to peanut size, often with small blisters at the top, individual blisters may form, individual lesions fade in about 1 week, but new lesions often occur continuously, with self-induced itching. ⑤ Frictional blisters: local blisters and blisters occur as a result of longer-term friction and pressure. It often occurs in areas of pressure or friction, such as the palms of the hands and feet and plantars. The blisters and blisters are thick-walled and do not break easily, with no surrounding redness and a negative Ney’s sign. Small blisters usually have no conscious symptoms, but there is often discomfort or pain when there are large blisters. Diabetic maculopathy can be the first symptom in diabetic patients, so it is easy to be misdiagnosed and mistreated, especially in older patients with insidious diabetic symptoms. This requires clinicians to be aware of diabetes and its complications, and also reminds dermatologists to always pay attention to blood glucose and urine sugar checks when encountering maculopathy, especially in middle-aged and elderly patients.