Abstract: An apparatus for measuring the shape and size of a rotary tool is provided which includes a tool rotation unit for rotating the tool around the tool axis, a tool moving mechanism for moving the tool in the axial direction, a measuring head having a line sensor, and a calculation control unit. The measuring head can be moved at a rate of a predetermined angle around a lateral shaft, located in a direction perpendicular to the axis of the tool, with one end of a measuring area of the line sensor as a center. Upon measuring the tool in terms of its shape and size, the aforementioned end of the line sensor is located in a position a given distance inside the aforementioned end of the tool, the line sensor is moved for every predetermined angle around a lateral shaft, with one end of the measuring area as a center, and measured values are fed to a computer through the line sensor, while the tool is rotated around its axis for every predetermined angle.