Abstract: The formation mechanism of landslide barrier dam is complex, mastering the dam deposit characteristics is of great significance for the breach risk assessment.Based on a physical model experiment, we studied the effects of slope gradient, landslide material composition and volume on the sliding movement process and deposition characteristics.The results show that the duration of sliding movement becomes shorter with the increase of particle size and slope gradient.The importance ranking of influencing factors for the single-particle landslide's speed in the first section is particle size, slope and volume, and in the middle and end sections is particle size, volume and slope.The speed of the mixed particle landslide in the first and end sections is mainly affected by the slope.The length of the barrier dam of single particle increases with the volume, especially the increasing rate is obvious under steep slope, and the width increases with the volume and particle size, and both increase rates are sensitive under steep slope.The logistic regression analysis of experimental data shows that the importance order of influencing factors for barrier dam height is particle size, volume and slope gradient.For the barrier dam of mixed and stratified particle, its length has no obvious correlation with the slope gradient, while its width and height increase with the slope gradient.