So why would a dog urinate when you approach it? Why is your puppy peeing whenever it gets excited?
It's called submissive wetting or excitement urination and it's common.
What we may consider inappropriate peeing is actually a way for dogs, especially puppies to show submissive behavior. A pet that is perfectly house trained may still urinate when greeting you or other visitors. I know that when I visit my brother's place, I should wait outside, let his dog run to me, and let it pee before we head inside. This is a well-trained, perfectly housebroken dog, but still subject to submissive urination. Actually, I think it's a combination of submissiveness and excitement and I touch on the excited dribbling further down.
You might be tempted to interpret the puppy peeing as the result of too much excitement but, for the most part, it's a show of respect. In the pet's mind, it's deferring to your higher rank or leadership.
This kind of dribbling urine often happens with puppies who haven't learned other ways that dogs show respect. Submissive urination from an adult dog is usually the result of insecurity -- pets that have been ignored or abused (such as those raised in a puppy farm) are more likely to submissively urinate.
Often, uncontrolled puppy peeing can indicate that it is overly sensitive or is or was mistreated -- and it now has an uncontrollable urge to constantly apologize (by being submissive and deferring to your authority). Submissive urination can be caused by too much punishment, which creates fear, or delayed punishment which confuses the puppy.
TREATING SUBMISSIVE URINATION
What can you do about submissive urination? The best thing to do is ignore it. If you get angry with the puppy, it will feel the need to pee again, and you'll create a negative cycle. If you praise or reassure your pet, you may be reinforcing the behavior. So again, just ignore it (but clean it up, obviously).
To prevent submissive urination, you need to build up your puppy's confidence while providing other ways for it to show respect. many people find success by teaching the dog a few obedience exercises... in a caring way. Once a pet can earn praise by obeying some commands, and learn to great people by sitting and shaking a paw, they will often no longer feel the need to urinate.
In an adult dog, excitement urination can indicate a problem, but for puppies it's very common. It's generally caused by a lack of bladder control and the puppy is usually not aware that it's even peeing. As your dog matures and develops better bladder control, the unexpected and unwelcome dribbles will disappear.
If you get angry, your pet won't know why, and the excitement pee and quickly turn into submissive urination. as it tries to make you happy.
TREATING EXCITEMENT URINATION
Prevention is the best policy for dealing with excitement urination. Try to observe and identify the things or activities that overly excite your puppy and either eliminate them, or desensitize your pet to them. For example, a puppies will often get excited and pee when the owner returns from being away. If this is the case, simply ignore your dog (don't even make eye contact) for a few minutes when you return. After several minutes, leave your home again for five to ten minutes, then return and ignore the dog again. Keep repeating the process until the puppy becomes used to the procedure or, if you're really lucky, bored. When your pet is no longer overly excited, calmly greet it. If it starts to show signs of excitement, or you notice the dreaded dribble, continue the leaving and returning procedure. It may also take a few days of practice.
If excitement urination also happens when guests come to visit, ask the willing visitors to use the same procedure as above.
While using the above training method, remember to ignore any excitement urination -- do not scold or reassure the puppy.