Itchy skin on the limbs may be caused by atopic dermatitis, tinea cruris and other causes. 1. atopic dermatitis: atopic dermatitis may be related to genetic, immune abnormalities and other factors, mainly in the limbs, trunk, eyelids and other parts of the body, mainly manifested in the skin surface erythema, papules, papules, dryness and other symptoms, accompanied by intense itching. 2. Tinea pedis: tinea pedis is a skin disease caused by fungal infection, mainly manifested as blisters, papules, vesicles, scales and other symptoms on the skin surface, accompanied by a certain degree of itching. The itchy skin of the limbs may also have other causes, it is recommended to go to the hospital in time to improve the examination, clear the cause of the disease to give targeted treatment.