The disastrous impact of a tailings dam failure is more far-reaching than that of a water retention dam failure. This paper analyzes the movement characteristics of mudflow during a tailings dam failure using physical models based on the Wadugou tailings impoundment. The physical models were built according to the similarity laws to investigate an overtopping dam failure under natural conditions and when additional protective measures were used. Based on the experimental results, the dam breach size, the breach flow discharge, flow velocity, downstream inundated area, and tailings deposition volume are all reduced by preferably protecting and maintaining the tailings dam embankment to mitigate the destructive effects of a potential dam failure. Finally, the time required for safe evacuation for the Wadugou tailings impoundment area is given.