Yes, goldfish have backbones. In fact, all fish have a backbone. They need this bone to swim. Not only does a goldfish have a backbone, but it has many other small bones inside. Each one of these bones is crucial to core functions. One of the most important bones is the one that connects the bladder to the ear. This is what enables goldfish to have an excellent sense of hearing. These bones are extremely small. They do not have any large bones inside their body.