A horizontal machine tool (1) includes a base frame (10) where workpiece support faces (11c) for supporting a workpiece are formed at front portions; an X-axis saddle (20) attached to a back-face portion (12b) of the base frame (10) through an X-axis movement mechanism (50) universally slidably in a left-right direction; a Y-axis saddle (30) attached to the X-axis saddle (20) through a Y-axis movement mechanism (60) universally slidably in an up-down direction; and a spindle device (40) attached to the Y-axis saddle (30) through a Z-axis movement mechanism (70) universally slidably in a front-rear direction. According to this configuration, it is possible to make a whole of the horizontal machine tool a small size and lightweight and to enhance machining accuracy of the workpiece.