Itchy skin on both thighs can be caused by neurodermatitis, ringworm and dermatitis eczema. 1. Neurodermatitis: is a chronic inflammatory skin disease, in the clinical mainly manifested as local skin thickening, moss-like changes, the surface can be covered with scales, the surrounding can be seen to varying degrees of hyperpigmentation, and accompanied by intense itching. 2. ringworm: is due to the thigh part of the skin infection ringworm bacteria and lead to a kind of skin disease, due to a certain degree of contagious, can be through scratching and close contact to spread, can be in the body of the onset of a number of places, the main clinical manifestations for the itching of the skin and the border of the clear lesions. 3. Dermatitis eczema disease: mostly localized because of skin or respiratory tract contact with sensitizers and the occurrence of metamorphosis, in the clinic can be manifested in all parts of the body skin can appear redness, pimples, erythema, as well as itching and other symptoms. The cause of itchy skin on both thighs is more complex, it is recommended that the patient to the hospital, the specific circumstances need to ask the doctor for an interview after treatment.