To provide a movable-spindle machine tool and a machining system that are simple in construction, can feed workpieces while checking their rotation about the main spindle axis, and have transfer means on which foreign matters are hard to deposit.

This movable-spindle machine tool comprises a main spindle 5 having a virtually vertical axis of rotation, a headstock 4 journalling the main spindle 5 and movable at least in the axis direction of the main spindle 5 and in a direction perpendicular to the axis thereof, a chuck 6 disposed at the lower end of the main spindle 5, and transfer means 31, 32 positioned at least near either end of a machine tool bed 10 in the direction perpendicular to the axis of the main spindle 5, provided with a gripping part for gripping a workpiece, and adapted to move between a position wherein it can pass the gripped workpiece to the chuck 6 and a position wherein it can deliver this workpiece out of the machine tool. The transfer means 31, 32 can feed the workpiece from the chuck 6 while checking its rotation about the axis of the main spindle 5.