How can we stop our cat attacking our new Yorkie puppy?

you could keep them seperate from each other or just try and get them to stay near each other.
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im not sure, if he's an outdoor cat, then just leave 1 window open to a room and do not allow the dog in tht room, becos if they fight they both mite get injured, xx.
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I'd keep a squirt bottle or a water gun with a good powerful stream nearby…..see if THAT works to deter the cat when she wants to pick on the puppy. I'm not really a cat person….but know folks who used this idea to train their cats to stay off kitchen counters & tables.

Might want to ask this in the Cat forum, just to see if anybody knows a better way to train a cat

Enough wet fur in return for pestering the pup & chances are, she'll leave well enough alone.

That, or you could figure out a way to keep the cat seperated from the pup, until the pup gets a little bigger & learns how to assert himself more.
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What did your pup do to provoke this? It's unusual, I'd think, for a cat to randomly attack a puppy? However, now this has happened, maybe your puppy will steer clear of your cat. Meanwhile, I think you need to have a cat area, and a dog area, if possible. My neighbours had three cats and the same number of dogs. Cats 'lived' upstairs (when their owners weren't around), gate across the stairs so the dogs couldn't get up there but they could come and go if needed. The cats came down during the evening.

Obviously when you are not around, you will have to make sure the cat can't get to your puppy, and vice versa. Otherwise I'm not sure what to suggest.
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He probably invaded her "personal" space and there is no way you can guarantee that won't happen again with a young puppy. I don't think a three-year-old cat is likely ever to adjust to a dog - the best you can hope for is a state of armed neutrality where they both learn to put up with each other. Unfortunately there will probably be injuries in the meantime, and because of their respective ages and the fact that cats do lash out if they feel threatened, it is probably the dog that will get injured. If you can't keep them completely separate until the dog is big enough to defend itself, it may be best to surrender one of them.
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This totally happened to me the other day lol. My cat went psycho chasing after my Great Dane. It was scary as hell at the time because Ive never seen my cat act like that, and my dog was knocking everything over to get out of her way. My dog got a couple nasty scratches on her back leg that I took her to the vet to have looked at. But you would think my dog would just turn around and defend herself, no no, not my massive dane against my little cat. She's such a sweet baby. Needless to say, if this event happens again my cat will become an 'outside' cat. lol.
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Mayhem In my Home