The baby patting the thigh, may be self-conscious performance, local itching and other factors. 1. Self-consciousness: baby patting thighs may be a sign of self-consciousness, in the hand patting will have a sense of accomplishment, repeated patting is a symptom of self-consciousness, if it is not accompanied by other manifestations, generally do not need special treatment and therapy. 2. Localized itching: the baby appeared to pat the thighs of the situation, may be due to the thigh part of the itching caused, but because the baby is still relatively small, will not be through the scratching way to relieve the itching, may be able to make use of patting the thighs of the way, so as to improve the symptoms. The baby pats the thigh, there may also be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.