If there is a pimple on the dog's belly, it may be the dog's belly button. If the pimple grows suddenly, it may be a pimple formed by the hair that the dog licked into the belly or caused by other diseases. It is best to Go to the hospital for a checkup. If it is a dog’s belly button, you need to pay attention to whether the belly button hole has become larger. If it becomes larger, you need to go to the hospital for suture surgery to avoid bacterial infection. If a lump appears suddenly, you need to go to the hospital for examination in time to avoid delaying treatment because it is a tumor.