Zsa Zsa Gabor's husband, Prince Frederic von Anhalt, is fuming mad over his botched "facemakerover" ... and he's already talking lawsuit if his mug doesn't heal properly.
As TMZ first reported, za Prince claims a plastic surgeon botched a routine operation on his face ... which he told us has left him "looking like s***" -- and it's hard to argue.
Von A-hole told our photog yesterday what exactly went wrong with his face, and explained it's NOT a Botox problem -- it's actually worse. He added, if his moneymaker (in his opinion) never heals he will unleash a $10 million lawsuit.
You've been varned, docs.