A machine tool comprising: a main shaft including a chuck capable of opening and closing on a front end; a set means for setting a workpiece; and a conveyance means for conveying the workpiece between the set means and said main shaft, wherein the machine tool is configured so that the conveyance means includes a holding means for holding the workpiece and the workpiece is transferred between said chuck and said holding means by positioning a chuck central axis line of said chuck and a workpiece central axis line of said workpiece on a single line in front of said main shaft, said set means is provided behind said main shaft said main shaft is provided along an axis line direction so as to be capable of moving back and forth, a support that supports a tool for machining a workpiece so as to be capable of moving is provided in front of said main shaft, said tool is disposed in front of the support, an area in front of said support is set as a machining area of the workpiece, said support is provided with an insertion part into which said main shaft is inserted, a range of movement of said main shaft is delimited from a position where said main shaft is inserted into said insertion part and said workpiece is disposed within said machining area to a position where a space for transferring the workpiece between said holding means and said chuck is formed behind said support, and characterised in that said set means is disposed so as to support the workpiece by positioning said chuck central axis line and said workpiece central axis line on a single line, and the posture of said holding means when transferring said workpiece with said set means is maintained when transferring said workpiece with said chuck and in that a shutter for blocking said insertion part is provided so as to be capable of opening and closing in order to separate said machining area and the rear side of said support. a main shaft including a chuck capable of opening and closing on a front end; a set means for setting a workpiece; and a conveyance means for conveying the workpiece between the set means and said main shaft, wherein the machine tool is configured so that the conveyance means includes a holding means for holding the workpiece and the workpiece is transferred between said chuck and said holding means by positioning a chuck central axis line of said chuck and a workpiece central axis line of said workpiece on a single line in front of said main shaft, said set means is provided behind said main shaft said main shaft is provided along an axis line direction so as to be capable of moving back and forth, a support that supports a tool for machining a workpiece so as to be capable of moving is provided in front of said main shaft, said tool is disposed in front of the support, an area in front of said support is set as a machining area of the workpiece, said support is provided with an insertion part into which said main shaft is inserted, a range of movement of said main shaft is delimited from a position where said main shaft is inserted into said insertion part and said workpiece is disposed within said machining area to a position where a space for transferring the workpiece between said holding means and said chuck is formed behind said support, and characterised in that said set means is disposed so as to support the workpiece by positioning said chuck central axis line and said workpiece central axis line on a single line, and the posture of said holding means when transferring said workpiece with said set means is maintained when transferring said workpiece with said chuck and in that a shutter for blocking said insertion part is provided so as to be capable of opening and closing in order to separate said machining area and the rear side of said support.