The loss of life risk evaluation model for dam break is built in this paper. By using an improved Monte Carlo method, the overtopping probability induced by concurrent flood and wind is calculated, and the Latin Hypercube Sampling is used to generate random numbers. The Graham method is used to calculate the loss of life resulting from dam failure. With Dongwushi reservoir located at Hebei Province taken as an example, the overtopping probability induced by concurrent flood and wind is calculated as 4.77×10−6. Loss of life is 24 220 when the warning time is 0.25–1 h and flood severity understanding is vague, which indicates that the risk is intolerable. The losses of life under three other conditions are tolerable: warning time 0.25–1 h, and precise flood severity understanding; warning time more than 1 h, and vague flood severity understanding; warning time more than 1 h, and precise flood severity understanding.