This is actually the most common question from dog parents (among tons of ones I get everyday), so I've consulted with some trustworthy experts (from PetMD and DogTime), trying to give out here the most reliable answer for you. So please read this report carefully!
How Often Should a Puppy Poop? How many Dog Poop is NORMAL?
It is normal for a puppy to poop between 1 and 5 days each day. Puppies generally defecate more often simply because we are feeding them more often. In fact, according to DogTime puppies should be fed 2 to 4 times the amount you would feed an adult dog. This is due to the pupping needing more calories and nutrients to grow and have energy.
Depending on your schedule you may end up feeding your puppy 3 or 4 days each day and that means he will have to poop right after he eats.
How many times a day should a dog poop?
Once your dog has reached adulthood (usually at one year-of-age) you will cut back how much food you are feeding him on a daily basis. Once the intake of food is lowered, your adult dog may only poop once or twice each day.
References: http://dogtime.com/puppies/218-feeding-puppies
How Often Do Puppies Poop? It Depends Greatly on the Food
Puppies need a lot of protein, nutrients, healthy fats, whole grains and added vitamins and minerals to support their development. When shopping for a quality kibble for your pup you will want to make sure it is not packed full of cheap fillers. This provides no nutritional value for your dog, but will make it poop more often...basically, junkie, filler-load foods equal more bathroom breaks.
High quality puppy foods, on the other paw, are usually formulated specifically for the growing needs of a puppy, some even state that the puppy's stools will be better formed and less smelly - this is because your puppy is utilizing the nutrients, rather than just pooping it out.
Tip: Feeding a puppy or dog table scraps may cause him to poop more.
When Should I Be Worried?
There are times that a puppy may go more than normal, or the consistency of the bowel movements are loose (diarrhea).
What is classified as diarrhea?
Look for liquid and frequent stools; however, diarrhea can also include blood or mucus in it (this can be a sign of a more serious condition). Other symptoms may also include fever, legarthy, dehydration, straining to go, loss of appetite and weight loss.
Diarrhea can be one of the first symptoms of some more serious conditions. These include:
References: http://www.peteducation.com/article.cfm?c=2+2090&aid=305
http://frontiervet.com/2012/07/30/coccidia-and-giardia-the-non-worm-parasites/
Puppy Not Pooping? Constipation May Be the Culprit
Another condition that can affect your puppy's bowel movement frequency is being constipated; this is when your pup's stools are extremely hard and dry. You may notice that your puppy strains when trying to poop and the frequency of going will be reduced.
Constipation in puppies can be brought on by many conditions, but mainly diet, stress and a lack of exercise are the main culprits.
References: http://mysweetpuppy.net/constipated-puppy/
Know Your Pooch
It's vitally important to always know your dog's bathroom habits and the consistency of its poop. Some diseases show symptoms of diarrhea listed on NolongerWild.com in the beginning stages, so know your pooch and always be sure to follow up with a veterinarian if you are concerned.