PURPOSE: To provide an X-groove cutting apparatus provided with horizontal direction copying device, in which a groove precision is improved while dealing with dislocation strain, etc., of an end surface in the longitudinal direction of a steel material to be cut and the arranging work setting a torch for cutting the beveling is precisely and efficiently executed in the X-groove cutting by gas.

CONSTITUTION: In a travelling carriage 20 travelled in the longitudinal direction of the steel material 10 to be cut, a traversing carriage 21 which can traverse to the right and left sides is provided. In the carriage, a vertical sliding mechanism 29 of a vertical arm 7 is provided, and in the vertical arm 7, vertical direction copying device 8, an upper torch block and a lower torch block are provided. In the traversing carriage 21, the side direction copying device 9 is fixed and an elastic pushing mechanism for pushing the traversing carriage 21 from the side direction to the steel material to be cut with a fixed pressure is separatly provided.