A waveform monitor is a special type of oscilloscope used in television applications. It is typically used to measure and display the level, or voltage, of an analogue video signal, regardless of its format (e.g. NTSC or PAL), with respect to time.

The level of a video signal usually corresponds to the brightness, or luminance, of the part of the image being drawn onto a regular video screen at the same point in time. A waveform monitor can be used to display the overall brightness of a television picture, or it can zoom in to show one or two individual lines of the video signal. It can also be used to visualize and observe special signals in the vertical blanking interval of a video signal.

A waveform monitor is often used in conjunction with a vectorscope, and both functions are often combined into the one device.