Blisters are known as blisters. Itchy small blisters on the calves are usually caused by acute eczema, papular urticaria, contact dermatitis, herpes zoster and other factors. 1. Acute eczema: eczema patients in the acute stage of blisters, mainly due to local vascular exudation and edema, sometimes may be accompanied by exudate and obvious itching. 2. papular urticaria: papular urticaria is an inflammatory skin disease caused by insect bites on the skin, the rash is mainly manifested as bright red papules with blisters in the center and obvious itching. 3. Contact dermatitis: It is an allergic or irritant reaction that occurs after the skin comes into contact with sensitizing or irritating objects. It manifests as localized redness of the skin, papules, blisters, or even vesicles, and will be accompanied by varying degrees of itching. 4. Herpes zoster: usually caused by the activation of varicella zoster virus. When the immune function decreases, such as suffering from malignant tumors, the use of immunosuppressant drugs, other viral infections, etc., the latent virus is activated, resulting in the appearance of erythema and blisters on the calves, accompanied by pain, tingling and itching and other symptoms. If the small blisters on the calves are itchy, it is recommended to go to the hospital in time to get a clear diagnosis and symptomatic treatment.