The pain on both sides of the waist may be related to the following causes: 1. Acute lumbar sprains may exist, often seen in patients who have previously lifted heavy objects, and then suddenly feel pain in the waist during the process of lifting. 2. The fatigue injury is produced. The patient may feel special pain on both sides of the waist when standing up or bending over time. 3. may be caused by lesions related to the urinary system, such as in the presence of acute glomerulonephritis, pyelonephritis, ureteral stones and other diseases, may show this symptom. 4. may be caused by infectious diseases, most commonly in the process of the onset of epidemic hemorrhagic fever, may have very severe pain in this area.