A waveform display device includes: an operation accepting unit for accepting operation by a user; and a display controller for generating waveform display screen including a program pattern waveform for program control and an actual measurement waveform based on measurement data obtained as a result of the program control, with the program pattern waveform and the actual measurement waveform being superimposed on each other, and a cursor indicating a section between a past time area showing a program pattern waveform and an actual measurement waveform in the past time and a future time area showing a future program pattern waveform. The operation accepting unit is configured to accept scroll operation for changing a position of the cursor in the waveform display screen. The display controller is configured to change the position of the cursor in the waveform display screen in accordance with the scroll operation.