BCG vaccine cannot eradicate bladder cancer. BCG vaccine is usually used to prevent tuberculosis, and the inoculation of BCG vaccine can make the body produce specific immunity to Mycobacterium tuberculosis, which can prevent the bacteria from reproducing in the body, thus preventing tuberculosis; the purpose of bladder instillation of BCG vaccine is to minimize and delay the recurrence and progress of bladder cancer, but it cannot eradicate bladder cancer. Bladder cancer is usually caused by a combination of multiple factors, resulting in malignant tumors on the bladder mucosa, which may have symptoms such as difficulty in urination and hematuria. Patients can go to the hospital for specific examination and be treated by means of radiotherapy and surgery. Bladder cancer patients are suggested to go to the hospital for treatment as early as possible so as not to delay the condition. Normally, they can eat more fresh vegetables and fruits, don’t smoke and keep a positive and optimistic mindset.