Abstract: A finite volume model based on structured grids is proposed for numerical simulation of dam-break flow over complex terrains with irregular boundaries in the study. In the proposed model, HLLC's approximate Riemann solution is used to compute the flow flux based on the two-dimensional shallow-water equations with conservation. The spatial and temporal precisions of the model are increased to the second-order precision by the MUSCL-Hancock method. Slope source terms and friction source terms are discretized in order to guarantee the model's stability. A robust procedure is introduced to efficiently and accurately simulate the movement of wet/dry fronts and water flow characteristics of complex terrains with irregular boundaries. Finally, flume experiments, physical models and actual case computation are used to verify the proposed model. Numerical results of dam-break flow from different test examples are highly consistent with observations and numerical results obtained by existing models, indicating that the proposed model has the higher stability and precision for a wide range of applications.