Double lower limb weakness may be caused by overwork of the lower limbs, or it may be caused by lumbar intervertebral disc herniation, arteriosclerosis occlusive disease of the lower limbs, lumbar spinal stenosis and other reasons. 1. Excessive exertion of the lower limbs: if the lower limbs walk for a long time and excessive exercise will lead to the lower limb muscles in a state of tension for a long time, and the lower limb muscle lactic acid secretion will be increased, the patient will appear the performance of the lower limbs soreness and weakness. 2. Lumbar intervertebral disc herniation: Lumbar intervertebral disc herniation is caused by degeneration of intervertebral discs, lumbar spine injury, abnormality, lumbar spine developmental abnormality and other factors. Patients will manifest as lumbar pain, sciatica, lower extremity numbness muscle radiating pain, some patients will also appear lower extremity weakness, so patients will manifest as double lower extremity soreness and weakness. 3. Lower extremity atherosclerosis occlusive disease: the etiology of lower extremity atherosclerosis occlusive disease has not been clearly defined, is considered to be hemodynamic changes, arterial wall lipid metabolism disorders and other factors. Patients will manifest as numbness of the lower limbs, skin weakness, pain, some patients will also have intermittent claudication, so patients will be manifested as double lower limb weakness. 4. Other: patients with bilateral lower limb weakness are also considered to be lumbar spinal stenosis, hypocalcemia and other diseases. If the lower limbs are overworked leading to double lower limb weakness can not be treated, usually after rest can be relieved. If it is a disease caused by the weakness of the lower limbs, you need to consult a doctor in a timely manner, and follow the doctor’s instructions to take appropriate measures to treat.