Is it gunnah to be vegeterian?
Being a vegetarian isn't making meat haram though, nor is it claiming that it's haram. It's personal preference.
Being vegetarian is fine Islamically, Baji.
I think the intention also plays a part in it, though.
If you do not eat meat because you think it is cruel and inhumane to kill animals for food, then it is haram, because you're basically saying that what Allah has allowed us to do is evil and cruel, and that the prophet peace be upon him was also cruel for eating meat.
If you don't eat meat simply because you don't like the taste, or can't for health reasons, etc., then it's fine inshallah.