Blisters with itching on the thighs may be caused by contact dermatitis, eczema, herpes zoster and other diseases, as well as other diseases such as insect bite reactions. 1. Contact dermatitis: contact dermatitis is mostly an allergic reaction caused by skin contact with exogenous substances that cause allergy, and the patient will have intensive pimples, itching, erythema, and swelling. In addition, patients will also experience burning, headache and other symptoms. 2. Eczema: The cause of eczema is still unclear, and it is considered to be caused by a variety of factors such as internal causes. The main symptoms of patients are papules, edema, erythema, etc., but also oozing, vesicles, itching and other symptoms. 3. Herpes zoster: herpes zoster is mainly caused by zoster virus infection, the patient’s main symptoms are pain, papules, low-grade fever, etc., and some patients will also have itching and other symptoms. 4. Other: insect bite reaction, urticaria and other diseases can also lead to the phenomenon of blisters with itching on the thighs. Patients with symptoms of blistering with itching on the thighs should consult a doctor in time and follow the doctor’s instructions for treatment.