The invention relates to a sound-sensitive speed measuring device and method, and belongs to the technical field of measurement. The sound-sensitive speed measuring device which is used to measure thespeed of a moving steel plate, comprises a sound source and at least one measurement unit; the first sound source abuts against the steel plate; the measurement unit comprises at least two vibrationmeasuring sensors arranged in the first sound source, and distance between each sensor to the sound source is L; and when the steel plate moves rightwards at the speed v, a sound signal provided by the first sound source is spread to the two sides of the sound at the speed v along the steel plate, a time difference between time when the two vibration measuring sensors in the same measurement unitobtains the sound signal is t, and the moving speed of the steel plate is calculated via a formula.