First and second screens are set for a tool path display apparatus for displaying a path of the tip of a tool attached to a machine tool. The first screen displays the three-dimensional path of the tip of the tool obtained by synthesizing the position information of the drive axes of a 5-axis machine tool. The second screen displays the waveforms of the position deviations and current instructions of the drive axes in chronological order. When a part (line segment) of the three-dimensional path of the tip of the tool is selected on the first screen, the display attribute of the corresponding time area is changed on the second screen so that the time area can be identified.