Abstract: Movement of submarine landslide may sometimes result in catastrophic tsunamis. The generation process of submarine landslide-induced impulse wave is crucial to the study of tsunami. The generation of tsunami is mainly controlled by the geometry of the mass, sliding velocity, sliding angle and water depth. Based on these factors, underwater orthogonal physical experiment of rigid block is designed and implemented. The proportion of thickness to length of the sliding block ranges between 0.035 and 0.180. The sliding angle is between 10°and 16°, with the Froude number between 0.18 and 0.70. The analyses of the experiments show that the formation of original impulse wave is earlier than the cease of the slide. The original trough (the biggest trough) generates when the sliding velocity reaches the maximum value. The position of trough is nearly the position of the mass center when the velocity of the slide reaches the maximum value. The original impulse wave is typically characterized by big troughs and small peaks. The calculation formula of the maximum trough and amplitude are derived by regressing the input and output data of the experiments. The analysis results of the experiments deepen the understanding of the generation of the submarine landslide-induced tsunami, and provid fundamental and technical support for submarine landslide-induced tsunami prediction.