The first sentence doesn't sound right. Both the second and third sentences sound ok, but most people, at least in my part of USA, would say the second form- What do you like most about me?

"What do you like the most about me?" is correct.

What do you like the most about me? Is correct.

Hi, Joel. Your explanation makes it easier to understand. But may I ask one more question about the #1 , what if the word "'most" was gotten rid of and be like this "What do you like of me?" Is it still wrong?

Here's what's wrong about #1 and #3. #1: "most of me" refers to amount. Like: "how much of this cookie do you want?" "I want most of it." So, Q: "What do you like the most in me?" A: "I like your teeth and your left leg the most""... just very strange! #3: "Most in me" has a feeling that is closer to correct (#2). But it's just not how we say it, so it sounds awkward. (It's just one of those things that don't have a nice, clean rule to say why it's right or wrong.) ---- Hi Ethan. To reply to your edit: "What do you like of me" is much, much better than the original -- the original was just too weird :) This version "what do you like of me" is, again, better (because it's not sounding like "how much of my body do you like of me"), but still a bit awkward. Best to forget it, and repeat "what do you like most about me" a few times (or the also-ok "what do you like about me?"). Take care!