An operation limiting device for a machine tool comprising: an input control portion ; a drive axis designating means capable of designating two or three drive axes in different directions among a plurality of drive axes (Xa, Xb, Za, Zb); a coordinate system forming means capable of forming a two-dimensional coordinate system (A-B) or a three-dimensional coordinate system (D-E-F) by the two or three drive axes designated by the drive axis designating means; a limiting area setting means capable of setting a plurality of limiting areas (Ar(xa-za), Ar (Xb-Zb) ) based on information relating to each of the plurality of limiting areas (Ar(xa-za), Ar (Xb-Zb) ) input by the input control portion to limit an operation of a mobile body which moves by the two or three drive axes designated by the drive axis designating means in the two-dimensional coordinate system or the three-dimensional coordinate system, each of the plurality of limiting areas corresponding to the two or three drive axes designated by the drive axis designating means; a determining means capable of determining a drive axis by which the mobile body is in operation; and a limiting means capable of limiting the operation of the mobile body when the mobile body enters into one of the plurality of limiting areas, using the plurality of limiting areas set in the two-dimensional coordinate system or the three-dimensional coordinate system formed by the drive axis by which the mobile body is in operation, characterized in that the limiting speed is set to be a value lower than a normally set speed, the normally set speed being a speed corresponding to the set value of the magnified ratio of the handle operation, an inching speed or an automated operation mode designated speed. an input control portion ; a drive axis designating means capable of designating two or three drive axes in different directions among a plurality of drive axes (Xa, Xb, Za, Zb); a coordinate system forming means capable of forming a two-dimensional coordinate system (A-B) or a three-dimensional coordinate system (D-E-F) by the two or three drive axes designated by the drive axis designating means; a limiting area setting means capable of setting a plurality of limiting areas (Ar(xa-za), Ar (Xb-Zb) ) based on information relating to each of the plurality of limiting areas (Ar(xa-za), Ar (Xb-Zb) ) input by the input control portion to limit an operation of a mobile body which moves by the two or three drive axes designated by the drive axis designating means in the two-dimensional coordinate system or the three-dimensional coordinate system, each of the plurality of limiting areas corresponding to the two or three drive axes designated by the drive axis designating means; a determining means capable of determining a drive axis by which the mobile body is in operation; and a limiting means capable of limiting the operation of the mobile body when the mobile body enters into one of the plurality of limiting areas, using the plurality of limiting areas set in the two-dimensional coordinate system or the three-dimensional coordinate system formed by the drive axis by which the mobile body is in operation, characterized in that the limiting speed is set to be a value lower than a normally set speed, the normally set speed being a speed corresponding to the set value of the magnified ratio of the handle operation, an inching speed or an automated operation mode designated speed. <EOS>