I agree with Nanren that it's hard to answer this question without more context. We don't have a common, conversational word that means 冤枉 in English, so we usually say something different. For example, I remember a scene in a Chinese movie where a teacher says to her student, "You're being lazy again!" because the student isn't working. The student says "你冤枉我了!" Then he explains that he has already finished all his work. In English, if a teacher said "You're being lazy again!", the student would probably just say, "No I'm not!" or "That's not true!" If the teacher said, "As punishment, you have to do extra work now," the student might say "That's not fair!" Another example: I think in Chinese you could say 你冤枉我了 if someone accused you of stealing something, but you didn't really steal anything. In English, if you wanted to say that someone accused you of something you didn't do, you would probably say "He's lying about me" or "He's trying to get me in trouble" or you would explain the whole situation: "He said I stole his books, but I didn't!" You could use the phrases Nanren suggested (to "wrong" someone, or to "do someone an injustice"), but both of these phrases are rarely used by native speakers. They're somewhat formal/literary, and they don't sound very natural in conversation. We usually just find a different way to describe the situation.

That’s a common idiomatic expression in Chinese, but there is no all-purpose equivalent in English; the translation would be different in every situation / context. What exactly happened, and what is your relationship with the person you’re speaking with? In a typical situation, I might say something like “you’ve got me all wrong”. There are many other options depending on how polite (or rude) we want to be, and the extent of and motivation for the other person’s behavior / attitude.

You have wronged me. You wrong me. - But this may be a little more general in English. You do me an injustice (by saying ...) You have done me an injustice. . Any context to go with it?