Small blisters on the palm may be caused by herpes sweat, tinea cruris, contact dermatitis and other diseases. 1. Sweat herpes: the etiology of this disease is not completely clear, may be related to allergic rhinitis, dermatophyte infection, ultraviolet irradiation, mental stress and other factors. The main manifestation is the appearance of itchy blisters on the hands or feet, which may be accompanied by tingling and burning sensation, mostly occurring in the palms of the hands, fingers and other places. 2. Ringworm: this disease is mainly caused by the infection of ringworm of the genus Trichophyton, Epidermolysis bullosa and other dermatophytes, which can be transmitted through direct or indirect contact, and the common risk factors are hands in a wet state for a long time, improper use of antibiotics and so on. The patient’s palms will appear small blisters, flaking, dryness and other manifestations. 3. Contact dermatitis: the occurrence of this disease is related to contact with allergens, such as cleaning products, animal dander, rubber gloves and so on. The patient’s hands will appear itching, swelling, burning and other symptoms, at the same time there will be pimples or small blisters. There are other causes of small blisters on the palm (such as eczema, etc.), it is recommended to go to the hospital to improve the relevant examination, to clarify the specific causes, do not self-medication.