I have never seen it. I have seen many squirrels and other rodents, but I don’t think I have ever seen any of them get sick in that way. So my first thought is, no, squirrels can’t vomit. I imagine that they have the same problems horses do. But, after further research, it is possible for a squirrel to vomit, which is lucky for the little guy in the video above. Otherwise he may have died from alcohol poisoning.