Dogs and bunnies usually don't make suitable companions. Dogs are predators and rabbits are prey, so the combination can be lethal. Even if your dog doesn't go after the rabbit, some bunnies become so frightened of canines that they suffer heart attacks. However, certain dogs can get along with particular rabbits, especially if Fido doesn't have a strong prey drive.
The Right Rabbits and Dogs
If your bunny and dog are both easygoing, mellow animals, there's a chance they could get along. If your dog's breed or background includes hound or terrier ancestry, his innate desire to kill smaller animals is probably too strong to trust him with a bunny. For best results, introduce a young puppy or a senior dog to a full-size bunny, not a delicate baby or a dwarf breed. Puppies younger than the age of 3 months are still learning social cues, so are more likely to accept a bunny. Older dogs might have reached the "live and let live" stage.
Even if your dog and bunny seem to get along just fine, never leave them alone unsupervised. If you have to leave the room, even for a few minutes, either take one of them with you or otherwise separate them. It only takes a few seconds for a dog's prey drive to kick in and kill or seriously injure the rabbit.