Reversal hinge for notebook computer

The utility model provides a retroflexed hinge of a notebook PC, which can connect the display screen of the notebook PC with a mainframe. The retroflexed hinge comprises at least a vertical rotating shaft connected with the display screen, which comprises a plurality of springs to make the display screen retroflex vertically relative to the display screen and the springs are fixed by a plurality of screw caps; a first connecting trunnion mount, which can connect and fix the vertical rotating shaft with the display screen; a horizontal rotating shaft, which can connect the mainframe with the first connecting trunnion mount and has an external sleeve and an internal rotating shaft to make the display screen rotate horizontally relative to the mainframe; and a second connecting trunnion mount, which can connect and fix the horizontal rotating shaft with the mainframe.