Waking up in the middle of the night with numbness in the left foot is mainly due to the following aspects: First, for elderly patients with previous hypertension diabetes and arteriosclerosis, waking up at night with numbness in the left foot, if accompanied by reduced strength in the left foot, consider that the patient may have cerebrovascular disease or lumbar disc herniation, and need to go to the hospital to do a cranial MRI and lumbar spine MRI to clarify the problem. Second, for young patients waking up in the middle of the night after the numbness of the left foot, we should ask the patient whether there is a long-term posture of lying on the left side, if the long-term left side of lying, there can be long-term pressure on the left foot, because the peroneal nerve appears after the knee joint is relatively weak. After the compression of the peroneal nerve will appear numbness of the left foot, this time to give appropriate muscle massage, or activity of the lower limbs after the symptoms of numbness can be alleviated. Third, if you wake up in the middle of the night with paroxysmal numbness in the left foot, you should go for an EEG examination to find out if there are seizures.