Abstract: The sticking and rebound behaviors of particle impaction is crucial for the prediction of ash particle deposition. In this work, we use discrete element method (DEM) to study the effect of powdery layer coverage on the sticking and rebound behaviors of particle impaction. Especially, to account for the stochasticity, 50 similar cases are simulated for each set of parameters followed by statistical analysis. The result indicates that the powdery layer plays a major role in dissipating the kinetic energy of the incident particle. The curve of the sticking probability shows a fast drop as the incident velocity increases to a certain value. This critical incident velocity scales proportionally with the layer thickness. The size ratio, defined as the incident particle diameter versus particle diameter in the layer, is the key parameter that determines the mechanism of energy dissipation.