An improved multi-function office machine having a paper-discharging space cover at an opening of a paper-discharging space, to prevent inflow of foreign substances into the multi-function office machine though the paper-discharging space. The multi-function office machine comprises a main body, a flat bed disposed at an upper portion of the main body to set a document, a flat bed cover with one end hinged to the main body to open and close the upper surface of the flat bed, a paper-discharging space disposed at a rear side of the main body to receive a printed paper, and having an opening at a top, and a paper-discharging space cover hinged to the rear side of the main body to open and close the opening.