If you mean the leg that a drinking glass stands on, it is called the "stem".
If you mean the two bits (normally hinged) that hook over your ears when wearing a pair of eyeglasses, the are called "temples" (though in my experience, many people call them the "arms").
Ok. I think this needs a little more information, or at least an explanation. What legs are you talking about?
my glasses, u know the ones i wear, the leg broke