Bladder cancer mostly occurs in middle-aged and elderly people over 50 years old, and the incidence rate increases accordingly with age. To prevent bladder cancer, we can pay more attention to the following aspects: First of all, we should adhere to scientific dietary habits and eat more fresh vegetables and fruits. Try to eat less meat food because meat food can produce substances similar to aniline and benzidine in the process of metabolism in the body. It has been found that workers who are exposed to chemical materials such as aniline and benzidine have more bladder cancer. Secondly, those who have the habit of smoking should quit smoking as soon as possible. Studies have shown that people who smoke a lot have a higher concentration of carcinogenic substances in urine. Thirdly, we should increase the amount of water we drink. Because the amount of drinking water directly affects the concentration of urine in the bladder, which has an important impact on the occurrence of bladder cancer. The urine in the bladder of those who drink less water is bound to decrease, and the concentration of carcinogenic substances in the urine is correspondingly higher after excreting from the kidneys to the bladder. These high concentrations of carcinogenic substances will cause strong irritation to the bladder mucosa. At the same time, those who drink less water are bound to have longer intervals between urination, which creates favorable conditions for the reproduction of bacteria in the bladder. Most of the people who often have cystitis are those who usually do not like to drink water. The increase in the concentration of bacteria in the urine not only triggers cystitis, but also produces adverse stimulation of the bladder mucosa. Over time, the bladder mucosa can gradually develop from inflammation and erosion to cancer under the dual stimulation of bacteria and carcinogenic substances.