To reduce the overall length of a machine tool which changes workpieces by means of the movement of a spindle head, by reducing the stroke of the total movement of the spindle head.

A vertical lathe moves a spindle head 8 in the directions of X and Y axes and rotates a main spindle 9 so that a workpiece W is machined by the tool 7 of a tool rest 5. To change workpieces, the spindle head 8 is pivoted about the pivot 11 of a saddle 4 and moved in the direction of Z axis and a machined workpiece W is lowered onto a conveyor 12 at a removing part 14 while an unmachined workpiece W is gripped by a chuck at a mounting part 13. The conveyor 12 conveys a number of workpieces W in a line longitudinally along a straight line passing through the mounting part 13 and the removing part 14.