A machining simulation display apparatus displays, on a display screen, an image of a shape of a workpiece and a shape of a tool that machines the workpiece, and includes a display update unit to provide a command to combine, at a change point on a trajectory of the tool, an image of the shape of the tool displayed on the display screen and an image of the shape of the workpiece at a first display update timing at which the image displayed on the display screen is updated or at a second display update timing that is a time point after a lapse of a constant display update interval since the first display update timing, the change point being present between the first display update timing and the second display update timing.