Thigh pain in children may be a normal physiological phenomenon, or it may be a muscle strain, hip synovitis and so on. 1. Normal physiological phenomenon: children’s thigh pain, may be a normal physiological phenomenon, called growing pains. Growing pains are due to the child’s rapid growth and development, bone growth is too fast and the surrounding nerves and muscles grow relatively slowly, resulting in a kind of pulling pain. As the child grows older, the pain will gradually decrease. 2. Muscle strain: If a child suffers a muscle strain in the leg during strenuous exercise, it can cause the breakage of the muscle fibers as well as edema and oozing of the surrounding tissues, which will be manifested as local swelling and severe pain. 3. Hip synovitis: usually associated with a recent cold. Inflammatory reaction can cause local tissue edema, and compression of the surrounding soft tissues and nerves, which in turn leads to abnormal sensory function of the leg and restricted movement, resulting in thigh pain symptoms. Children’s thigh pain, there may be other reasons, it is recommended to go to the hospital in a timely manner, complete the examination to determine the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.