Large eddy simulation has been applied to simulate the compressible flow past one and two wall-mounted rectangle cylinders, respectively. The dynamic subgrid stress model is employed to approximate the subgrid scale effects. Flow past one single wall-mounted cylinder is used as an example to validate our code. Flow past two wall-mounted cylinders is chosen for investigating the variation of flow fields and drag coefficients under different heights of two cylinders. Our numerical results show that, with certain ratio of two cylinder height, their drag coefficient can be improved, which is important for practical building industries.