A hinge mechanism has at least one hinge assembly, a rail assembly and a sliding bracket. The hinge assembly has a hinge and a lifting seat. The hinge is adapted to pivotally connect a cover and a base of an electronic device. The lifting seat is attached to the cover and has a recess. The rail assembly has at least one rail seat having a rail slot. The sliding bracket is adapted to be deposited an input unit, is movably mounted between the hinge assembly and the rail assembly and has at least one upper sliding shaft and at least one lower sliding shaft. The upper and lower sliding shafts are respectively mounted in the recess and the rail slot. A side of the sliding bracket would be elevated by the lifting seat to allow the sliding bracket to be inclined to the cover, whereby the input unit is convenient for use.