Dogs sometimes bite and chew on their leash as a way to play or when they’re overstimulated, says Sunny. There are different things you can do to stop the behavior. “If your dog is an avid leash biter, I would recommend to first work on teaching them that biting the leash means we don't go for a walk,” Sunny says. “Start inside in a secure area, put the leash on the dog, and start to walk towards the door. As soon as your dog bites the leash, drop the leash and walk away. This will indicate to the dog that they won't get to go for a walk if they continue to bite the leash.” Another option is choosing a leash that isn’t fun or easy to chew like one made of chain or coated wire, Sunny says. She also suggests covering the leash in something that tastes bad, like apple cider vinegar. Biting the leash can also mean the collar or harness is uncomfortable, Gianella says. “I would first make sure the leash is not too heavy for the dog and the harness and the collar are fitting correctly. You should be able to fit two fingers under the collar and harness and it still be a little snug,” she says. If your dog is chewing on the leash out of excitement or frustration when you’re walking, she suggests rewarding the good behavior and not the unwanted activity. “You can mark and reinforce them for attention on you, being by your side, sniffing, or doing anything else other than chewing on the leash,” she says. “The more they are reinforced for everything but chewing on the leash, the less you'll see it.”