This invention is related to a dual-functional medium shredding machine structure, specifically designed for shredding or destroying paper printed with data to be destroyed, optical discs containing data to be destroyed, or expired credit cards. This invention mainly implements a pair of shredding roller blades with sharp teeth as shredding means, and is characterized by providing separate feeding inports, including a paper inport for feeding paper in an inclined orientation, and a disc inport for feeding discs in a vertical orientation, wherein the inports are each led to the same shredding roller blades such that, regardless of the type of substance being fed by the user, the paper or the discs can both be shredded by the shredding roller blades, and the shredded scraps are dispensed to separate collectors through an identical exit by means of an auto-revolving switch plate; and a touch switch at each of the inports such that, while feeding the paper or the discs, the touch switch activates the shredding roller blades to perform shredding task, and drives the switch plate so as to dispense shredded scraps of different substance into different collectors.