PURPOSE: To easily produce a proper coordinate dimension by instructing the display or non-display of the leader line of the coordinate dimension when a coordinate dimension line is produced.

CONSTITUTION: A write/rewrite control part 17 writes the coordinate dimension data on the measuring point pointed by a measuring point pointing part 14 into the drawing data displayed on a display 3 and also stored in a memory 16. A leader line display instructing part 18 functions when a writing command of the coordinate dimension is inputted through a command input part 12 and when the dimension position is pointed by a dimension position pointing part 15 and instructs the display or non-display of the leader line of the coordinate dimension. A display switch processing part 19 controls the part 17 in response to the instruction of the display or non-display of the leader line given from a leader line display instructing part 18 and then controls the display/non-display of the leader line to the drawing data which are shown on the display 3 and also stored in the memory 16.