An amending circuit of correcting bouncing misjudgment of a keyswitch includes a comparing unit, a predetermined voltage generating unit and a controlling unit. The comparing unit has a first input terminal, a second input terminal and an output terminal. The first input terminal is adapted to receive a triggering signal generated by the keyswitch. The predetermined voltage generating unit is electrically connected to the second input terminal and adapted to generate a first predetermined voltage. The controlling unit is electrically connected to the output terminal. The controlling unit is adapted to determine whether to execute polling application according to a comparison result of the comparing unit, and to generate a confirming signal while a polling result of the polling application is kept at a specific level. The confirming signal is used by an external processor to confirm that the keyswitch is actually triggered.