In the hardware-in-the-loop simulation, Laser Target Echo Simulator(LTES) is one of the most important equipment in the Laser Guidance Weapon System(LGWS). The model for the laser pulse features in time domain is a key technology in the LTES. A model of the laser pulse broadening in turbulent atmosphere was constructed. In the model, atmosphere was treated as multi-layer medium with different refractive index. The influence of medium with multi-layer for the laser pulse broadening mechanism, which is propagated in the multilayered medium, was analyzed. Then, the model of the target reflection was also constructed according to the characteristics of the target reflection. Two models were demonstrated by simulation. Moreover, the maximal pulse broadening of 10 ns was obtained when the distance of 10 km, the laser divergence angle of 1 mrad and wavelength of 1 064 nm was assumed. The result of planar target was calculated in final. This model can be applied in the real laser radar echo simulation.