The pain on the left side of the stomach near the waist may be caused by lumbar muscle strain, lumbar disc herniation and kidney disease. 1. Lumbar muscle strain: pain in the lower back is a typical symptom of patients with lumbar muscle strain, which not only causes pain in the lower back, but also causes muscle weakness and other symptoms. 2. Herniated lumbar disc: these patients may also experience the above symptoms. If the herniated lumbar disc compresses the lumbar nerve roots or even the spinal cord, it will cause a series of uncomfortable symptoms such as lumbar pain. 3. Kidney disease: Because the left side of the stomach near the waist is the part of the human body’s kidneys, therefore, the left side of the stomach near the waist pain may also be caused by kidney disease. Such as common kidney stones patients, there will be a side of the waist and abdomen obvious pain symptoms. Therefore, it is recommended that the patient go to the hospital in time, to clarify the cause of the disease, for treatment.