Can you use antibiotic ointment on cats?

Unless it is medicine given to you by a vet, then no. Human medicine is made for humans. Cats are much smaller than humans, so giving a cat human medicine can easily lead to an overdose which can ultimately kill the cat. If your cat needs treatment, take it to a vet where they can prescribe medicine that is safe to use on your cat.

As long as you make sure that they won't lick it off, then you can use a suitable amount on a small wound at home. I put some on our outside cat when he had a wound, and it worked just fine and he was great. It comes off on stuff when they rub though, so you might want to put some sort of bandage on there too.