Numbness of the feet when walking can be caused by the following reasons: first, lumbar disc herniation, serious lumbar disc herniation can lead to serious pressure on the nerve roots when walking, resulting in symptoms of numbness of the feet, which radiates from the buttocks, the back of the thigh to the back of the foot, the sole of the foot, the lateral calf numbness, then we should check the CT and MRI of the lumbar disc to diagnose. Second, lumbar spinal stenosis, lumbar spinal stenosis can also have nerve root compression, the symptoms of foot numbness when walking, can be accompanied by pain and discomfort in the buttocks, this time to check the lumbar spine X-ray, CT and MRI to diagnose. Third, pear-shaped muscle syndrome, pear-shaped muscle syndrome can also have the symptoms of foot numbness when walking, which is due to the sciatic nerve compression in the pear-shaped muscle and lead to foot numbness, then we should check the neuromyography of the lower limbs and physical examination to diagnose.