The relative alteration of WignerVille Distribution crossterm statistic was proposed for damage detection of guyed masts. And numerical analysis and experimental study were carried out with the case of the aeronavigating guyed mast in Fuling District. It was found that not only the shaft’s damage of different location and degree, but also the local damage of different type could be identified with the relative alteration of WCS accurately. The accuracy and sensitivity of the identification can be improved by increasing the guy’s initial pretensions. The damage identification test can quantify the damage extent of simulation. And it was indicated that the WCS index can identify the local damage of guyed mast and the results of damage identification were in good agreement with those of numerical analysis.