The more application of visualization techniques in medicine, geology and other fields is employed, but less use in structural damage detection area. This paper presents visualization of damaged rail, in which the damage has been identified via wavelet transform. First, a simulation of intact and single damages rail was carried out. Then, the displacement modes of intact and damaged rail are extracted and the displacement mode changes are obtained. Next, the wavelet transformation is applied to the displacement mode changes in rail and the abrupt changes of wavelet coefficients indicate damage. Finally, the damage detection results are visualized via volume visualization techniques. The results show that the low-order vibration modes of rail occur mainly in the lateral, the wavelet coefficient module maximums of mode changes indicate the damage placement, and the visualized damage detection results not only adequately show the original structure contour, but also enable the modality of damage index enough vivid to be accepted easily.