Why Does Your Dog Bark at Other Dogs?

When dog owners reach out to me and I ask why they’re seeking training, one of the most common responses I hear is, “When my dog sees another dog, they go crazy!” Though this outburst can feel embarrassing, stressful, and isolating, it is an incredibly common behavior that many people struggle with. The first step to changing it is understanding why it’s happening. So, if you’re one of the many owners who are tired of constantly watching for other dogs, gripping the leash to brace for the outburst, and rerouting your walks just to avoid a scene, this article is for you.

Though it can appear aggressive, not all barking stems from meanness. Barking is communication; it’s how dogs express their emotions. To understand what emotion your dog is trying to convey, take a look at their body language and behavior as a whole. Do they lunge wildly and excitedly at the end of the leash while barking? Do they dart away from the approaching dog, barking defensively? Or do they stiffen and stare intensely until – boom! – they explode into barking and lunging? To change your dog’s behavior, we first need to figure out why they’re reacting.

Below are some of the most common reasons dogs bark at other dogs. Where does your dog fit?

Overexcitement

For many dogs, especially young or high-energy ones, the sight of another dog is thrilling. They’re so excited by the idea of playing or interacting that they burst with energy through barking, jumping, and pulling. Even though their intent is friendly, this behavior still needs work. An excited dog can overwhelm or stress out another dog, leading to a negative experience for both. Plus, not every dog they see is going to be a playmate. Overexcited dogs need help learning how to manage their emotions and stay calm or that enthusiasm can easily turn into frustration.

Frustration

When an excited dog is held back repeatedly by a leash, a fence, or an owner, it can build up into frustration. Without clear direction or guidance, that pent-up energy can quickly boil over. You might see lunging, growling, biting at the leash (or even at the owner!), or redirected aggression toward the very dog they wanted to greet. Frustrated dogs need structure, outlets for energy, and clear expectations to help them handle disappointment and self-regulate.

Fear or negative experiences

Sometimes, barking is a dog’s way of saying, “Back off! I mean it.” Their goal is to create space and make the scary dog go away. While fear can be obvious (tucked tail, backing away, shaking), it can also come across as loud and intense. These dogs are often thrown into a fight-or-flight state, and because the leash takes away the flight option, they feel pushed into a defensive response. Some dogs develop fear after being attacked or overwhelmed, while others are simply underexposed to other dogs or genetically more anxious.

Lack of socialization or uncertainty

Proper early socialization helps dogs learn to view other dogs as normal, non-threatening parts of life. Without it, they may react with uncertainty or stress simply because they don’t know what to expect. A dog who hasn’t been exposed to other dogs, or hasn’t been guided through those interactions, may treat each new dog as a potential threat. That confusion can turn into barking, even if they don’t really want conflict.

Territorial or protective behavior

Some dogs are naturally more territorial or protective of their space, their owners, or areas they frequent. They might bark and react to dogs walking past their yard or to anyone who gets too close on a walk. Though I find most people jump to this conclusion, I rarely find that it is actually the case. A dog who is truly being protective of their owner or area is usually a confident dog who does not react to other dogs like this once taken out of the situation.

What can you do when your dog barks at another dog?

For fearful, nervous, or uncertain dogs, the goal is to slowly build confidence through counter-conditioning – pairing good things (like treats or play) with the presence of other dogs. Start at a distance where your dog notices the other dog but doesn’t react. Over time, gently close that distance while keeping your dog calm. Forcing interactions or letting unfamiliar dogs rush up can cause setbacks. Focus on showing your dog through calm, consistent exposure that other dogs aren’t a threat.

For overexcited or frustrated dogs, the key is structure and owner engagement. These dogs benefit from clear direction and a strong relationship with their owner. Teach them that walking with you is rewarding, and passing dogs are no big deal. Play with your dog, give them instructions, and keep their attention during walks. Start at a distance where they can succeed and gradually close that space as they become more focused on you and less interested in the other dogs.

Dogs with protective tendencies also benefit from consistent obedience training and leadership. They need to learn that it’s not their job to manage the environment and you’ve got that covered. By building trust and reinforcing your role as the leader, you help your dog relax and follow your directions.

In conclusion

Remember that changing your dog’s barking habit toward other dogs takes time, patience, and a bit of trial and error to figure out what works best for your dog. So if this all feels a little overwhelming or you’re not sure where to start, don’t hesitate to reach out to a professional trainer. Having guidance and support from someone who is experienced in reading canine body language, pinning the root cause/emotion, and creating a training program specific to your dog can make a huge difference. Happy training!