The invention provides a vibration error correction method applied to strip steel width measurement. A strip steel width measurement system comprises cameras, a strip light source, upright columns, rollers, an industrial computer, a laser range finder and cross beams; the two upright columns are respectively located at two sides of a roller way; two ends of each of two cross beams are respectivelyfixed onto the upright columns at the two sides of the roller way; the middle of one of the cross beams is equipped with the laser range finder and the two cameras; and the other cross beam is provided with the strip light source; and the cameras and the laser range finder are connected with the industrial computer. The laser range finder and the cameras are initialized; a relationship table about relationships between pixel scale values V and distances S between the cameras and strip steel, and the distance values W of two camera center positions are imported; a steel plate image is collected, and is processed, so that the number of pixels from a left camera image sensor center line position to the edge position of the strip steel and the number of pixels from a right camera image sensorcenter line position to the edge position of the strip steel are ML and MR respectively; the pixel scale values V corresponding to the distances S are applied; and a corrected strip steel width valueis calculated according to an expression that W+V*(ML+MR). With the method of the invention adopted, errors caused by the change of distances between CCD cameras and strip steel in strip steel widthmeasurement can be corrected conveniently and quickly, and therefore, measurement errors caused by vibration can be effectively offset.