Abstract: This application provides a measurement assembly, a measurement method, and a measurement system. The measurement assembly includes a support beam and a flush gauge. The support beam includes a reference surface used to fit against a measurement reference surface, and a track extending parallel to the reference surface. The flush gauge includes a main body and a measurement rod. The main body is slidably disposed on the track, and the measurement rod includes a first end and a second end disposed opposite each other. The first end is fixedly connected to the main body, the second end is used to abut against a surface of an object being measured, and the second end is able to movable toward and away from the first end.