Your first line of defense will be to bathe your puppy using warm water and dishwashing soap, which has proven very effective in killing fleas and is often used by dog groomers and breeders to treat flea problems. Fill the sink or tub with water to a level that will reach up to your puppy's neck. Submerse him completely so that the entire body is wet. Remove your puppy and place him on a towel and massage the dishwashing soap all over his body into his skin. Wet his face and massage the soap gently into his fur, careful not to get soap into his eyes. Then put him back into the water to rinse the soap out.

Try as hard as you can to keep his body submerged for a few minutes to guarantee that the fleas die. Wrap him up in a towel quickly and dry him to keep him from getting cold. Finally, go over your puppy's entire body with a flea comb. Keep a cup of boiling water close by to drop the fleas into. It may help to apply some vaseline to the base of the flea comb to keep the fleas from escaping.

To control your puppy's flea problem chemically, you'll need to turn to products specifically made to be gentle enough for puppies. Advantage and Frontline, for example, can be used on younger dogs than other brands. Products like Advantage and Frontline work by essentially immobilizing and killing fleas. They also kill any larvae the fleas have laid on your puppy so that the cycle of fleas is effectively broken.