Abstract: An electromagnetic wave proof cup structure for bra includes a first layer, a second layer and an intermediate layer joined to the first and the second layers. The intermediate layer contains metallic fiber so as to screen the electromagnetic wave and the contact area between the breast and the bra cup can be reduced effectively to decrease the hurt resulting from electromagnetic wave. The intermediate layer includes a first sheet piece and a second sheet piece and the two sheet pieces are attached to two lateral sides of the bra cup respectively in a way of extending upward so that the breast can be held upward and centrally disposed in the bra cup.