Dog growling is a natural instinct for dogs, but is only used when something is wrong.
This aggressive behaviour should never be tolerated. If your dog growls at you it means he sees you as a subordinate and not as his leader. This will undermine your whole relationship. Your pet must see you as the leader and respect your authority. If your dog starts growling at you, you must assert control and tell him no. This should begin when they are puppies.
At the first sign of your dog growling you should take him to a vet to rule out any medical problems. If he is given a clean bill of health, you may consider consulting a behavioral specialist. This is especially helpful if his aggression is stemming from experiences with a previous owner.
Make sure your dog understands the pecking order within the family. He needs to view all the humans as his superior. There are many simple ways to accomplish this. Do not allow your dog to walk through a door first. This lets him think he is the leader. If you allow him to sleep in the bed with you, he will think of himself as your equal. Make him lay at your feet if you must allow him in the bed. Do not allow your dog to eat first. The family should eat dinner before feeding your pet.
Make sure other members of the family participate in obedience training. Your dog needs to learn to obey them as well as you. If he does not follow their commands, you need to correct him and let him know that their authority is just as critical as yours. This can help prevent dog barking or growling, as well as to stop it in situations where your dog has become confused about pack rank.
To stop your pet from growling, you may need to work on his socialisation. Sometimes he is uncomfortable and afraid of other animals or situations, causing him to growl. If this is the case, consider gradually exposing him to new environments and other dogs. You may want to use a muzzle in the beginning. It may take some time for him to adapt, but if it works it will be well worth it.
If you hear your dog growling at any other time other than playtime you should consider starting aggression training. This could be a sign of a serious problem that you may not be able to handle alone. Consider working with a professional trainer. As an outsider to the situation, the solution to your dog growling problems may be quite obvious. A professional trainer often has experience working with such problems, and would know the best advice to give you.