To enable quick and easy visual recognition of an association between a signal waveform based on a display target signal and character information relating to the display target signal without causing wrong recognition of the association.

A waveform display device includes a display control unit that displays on a waveform display screen 11 signal waveforms W1-W4 based on display target signals and predetermined character information i1-i4 relating to the display target signals in association with each other. The display control unit performs: display processing A that, when sections satisfying a condition A exist in the signal waveforms W1 and W4 displayed on the waveform display screen 11, displays the character information i1 and i4 at predetermined positions in the vicinity of the sections satisfying the condition A, the condition A being that the levels of the corresponding display target signals rise to Hi levels; and display processing B that, when sections satisfying a condition B exist in the signal waveforms W2 and W3 displayed on the waveform display screen 11, displays the character information i2 and i3 at predetermined positions in the vicinity of the sections satisfying the condition B, the condition B being that the levels of the corresponding display target signals drop to Low levels.