The most common cause of pain in one side of the hip and leg is sciatica in the lower extremity. The sciatic nerve is the main nerve in the lower extremity, which emanates from the nerve root canal of the lumbar spine and reaches the lower extremity through the hip. When the corresponding inflammatory reaction, injury, compression and other conditions occur in the sciatic nerve, the corresponding symptoms are likely to appear. The common ones, such as lumbar disc herniation, lumbar spinal stenosis, and lumbar spondylolisthesis, can compress the nerve roots of the sciatic nerve and thus cause the corresponding symptoms. In the hip where the sciatic nerve exits the pear-shaped muscle, the presence of compression and inflammatory response stimulation can also lead to the corresponding symptoms. The presence of corresponding neuritis, injury, strain, etc. in the trunk of the sciatic nerve can also produce corresponding symptoms. It is recommended that patients go to the hospital for a detailed examination to locate the specific part of the sciatic nerve where the corresponding abnormality occurs, and then take the appropriate treatment.