Dog Tail Wagging During Sleep and Other Sleep Movements! (2024)

A yellow Labrador puppy sleeping on a bed on top of a white comforter.

Many people enjoy watching their dogs sleep and knowing they are resting peacefully.

If you watch your dog long enough, you may notice him wagging his tail, barking, or moving slightly while he’s in a deep sleep.

This is actually common and usually a reaction to a dream. In rare cases, it may be a sign of a health problem.

Why do dogs wag their tails when sleeping? Dogs tend to wag their tails in their sleep when they are experiencing REM sleep. This is the part of the sleep cycle when dogs are in the deepest sleep. They wag their tails because they are relaxed and happy or while they are in the midst of a  dream.

If you notice your dog is wagging his tail in his sleep and are wondering why, read on to learn more about this type of behavior. 

Dog Movements During Sleep

Dogs make a lot of movements while they are sleeping. Just like humans tend to move when they are in deep sleep or are dreaming, dogs can do the same.

Understanding these movements will allow you to know when your dog is sleeping comfortably or when there may be a problem. 

REM Sleep in Dogs

REM sleep is the deepest phase of a dog’s sleep cycle. Humans and other animals also experience REM sleep. REM stands for rapid eye movement, which occurs during this sleep phase.

When dog’s experience REM, they may wag their tails or have other involuntary movements.

Tail Wagging During Sleep

Tails wagging during sleep is common in dogs, and it usually occurs when they are completely comfortable, relaxed, and happy.

Dogs may also wag their tails in their sleep if they are dreaming.

Barking While Asleep

When dogs bark in their sleep, it usually means they are dreaming. Dogs go through many of the same stages of sleep as humans, and they dream in the deepest phase.

They may bark as a reaction to something they are dreaming about.

Twitching or Shaking During Sleep

The most common reason why dogs shake or twitch in their sleep is because they are dreaming. They can also twitch as their nervous system starts to adjust to being asleep.

In rare cases, dogs may have seizures in their sleep, which may look like severe twitching or shaking.

Paws Moving While Sound Asleep

Dogs often move their paws while they are sound asleep because they are dreaming.

They may also move them to switch sleeping positions or as a result of the nervous system responding to certain stimuli that the dog may not be aware of.

If the shaking is severe, it may be a sign of a seizure or another serious health problem. 

Do Dogs Actually Have Dreams?

There have been many studies that show dogs do dream. Scientists also believe that dogs dream in a way that is similar to humans.

They replay events and memories in their minds, and their dreams are often things that they remember well or that affected them greatly.

In fact, in an interview with People, Dr. Deirdre Barrett, who is a teacher and a Clinical and Evolutionary Psychologist at Harvard Medical School, explained that dogs usually dream about happy moments with their owners and the people they love.

How Do You Tell If Your Dog Is Having a Nightmare or a Dream?

Bulldog Sleeping on Couch

Dogs can have good dreams and nightmares just like people. Dogs react to good dreams the same way they react to good situations in life. They may perk their ears up and wag their tails.

When dogs have nightmares, they can seem distressed in their sleep. They may whine or bark, twitch a lot, and have heavy or fast-paced breathing. 

Do Dogs Dream About Their Owners?

Scientists believe dogs dream about their owners and the people they love.

Just like people, dogs dream about the things that happen to them and the people who are a part of their more memorable experiences.

Do Dogs Wag Their Tails on Purpose?

Dogs can wag their tails on purpose, but they may also wag them involuntarily. Dogs use tail wagging to show that they are happy or afraid.

They can also use their tails to spread pheromones and to communicate with their owners and other dogs.

Does a Wagging Tail Always Mean Happy?

Dogs don’t just wag their tails when they are happy. They can also wag their tails when they are scared or when they want to communicate with each other.

Different types of tail wagging and different tail movements mean different things. Sometimes owners are able to read their dog’s tail wagging movements to determine their mood.

Related Questions:

Why Does My Dog Howl at Night?

The most common reason dogs howl at night is because they are lonely and suffering from separation anxiety.

They may also howl as a way to communicate with other dogs, to express pain or fear, and to alert other dogs or their owners that someone is nearby.

Why Does My Dog Pace at Night?

Dogs may pace at night because they are restless and are trying to get comfortable or because they are bored.

Elderly dogs that pace often may be suffering from cognitive dysfunction, which is a disease similar to dementia in humans. 


Like humans, dogs do not stay completely still when they sleep.

Dogs may wag their tails, whine or bark, or even move around while they are sleeping because they are dreaming or because they have muscle spasms while entering into the deeper phases of sleep.

Most movements are not cause for concern.

If your dog seems to be moving due to pain or if you think your dog may be having seizures in its sleep, make an appointment with a veterinarian as soon as possible.