Yes sweet potatoes are good for dogs.
You can feed your dog some sweet potatoes in moderation.
Just don't feed the dog too many sweet potatoes at a time or the dog may get a stomach ache and possible diarrhea.
But in moderation feeding the dog some sweet potatoes is perfectly okay and fine and the dog will have better health as a result of eating sweet potatoes.
Just like sweet potatoes are healthy for humans the sweet potatoes are great for dogs health as well.
My dog loves sweet potatoes and eats them whenever I eat them and sometimes I just chop a sweet potato up and add it to his dog food and he loves it.