Prostate cancer can cause back pain; as prostate cancer is a tumor that metastasizes easily, back pain can occur when lumbar metastasis is detected from prostate cancer. Prostate cancer is a malignant tumor that occurs in the prostate gland. Early prostate cancer is not experiencing low back pain when there is no lesion confined to the prostate gland and no metastasis to distant sites. As the disease progresses, prostate cancer will have distant metastasis, and the common metastatic site is the spinal part, including lumbar and thoracic vertebrae; when prostate cancer metastasizes to the lumbar and thoracic vertebrae, the destruction of bone, nerve involvement, and the decrease of weight-bearing capacity will cause the patients to have lumbar pain and radiating pain in the legs, and even pathological fracture. When the patients have unknown lumbar pain and leg pain, they need to go to regular hospitals in time to improve the relevant examinations, make a clear diagnosis, and follow the doctor’s instructions for standardized treatment.