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Abstract. The propagation characteristics and parameter sensitivity of the landslide induced impulse wave in practical channel type reservoirs are investigated in this study. The twodimensional Saint-Venant equation and dry-wet boundary treatment method are used to simulate the wave generation and propagation processes in real reservoirs. In order to better reproduce the initial wave, a matching technique of initial wave between nearfield and far field simulation is implemented, while the nearfield wave generation processes are simulated based on full Naiver-Stokes equation. A real landslide induced impulse wave event is simulated with this technique and the propagation characteristics and parameter sensitivity are investigated. The simulation results and comparison between different cases indicate that the longitudinal shape of the channel-type reservoir is a crucial factor for propagation. Classical engineering methods which ignore this factor might produce improper estimation of the max wave height. IntroductionThe landslide induced impulse wave (LIIW) is a common but destructive disaster which happens generally in reservoirs and sea coast. In the mountainous area, many steep slopes locate at the bank of reservoir. Numerous events could trigger slope failure of these slopes, thereby massive landslide body might run into the water with high speed and thus cause destructive huge wave which will propagate to the upper and lower reaches in the reservoir. Comparing with LIIW in the basin-type reservoir, the LIIW in the channel-type reservoirs might be more danger as wave energy density of the latter is larger than the former at the same far field site.Heller and Hager (2010) [1] developed two models for both 2D LIIW and half-plane 3D LIIW. Their estimation is directly based on impact parameters and the distance between observation site and the impact site without explicit discrimination of the generation and propagation processes. In fact the generation process and the propagation process of LIIW are controlled by different physical mechanism and thus can be very different. The kernel mechanism of the wave generation is the energy transport and transform between landslide body and the water flow. Different energy magnitude and distribution lead to different wave form, while the energy dissipation in the inner generation zone is so strong that wave cannot sustains. The Naiver-Stokes equation instead of any depth averaged equation should be used to