Fine particles deposition widely exists in natural environment and industrial fields such as air pollution, metallurgy, coal combustion, and geothermal utilization. In this work, the effects of mass concentration of poly-disperse particles and inlet air velocity on particle deposition behaviors in the turbulent flow field were numerically analyzed. Results showed that the particle deposition probability density was not monotonic with the mass concentration. Starting from the third rough structure, the deposition probability density reached a maximum at the mass concentration of 2.78 g/m(3). The non-dimension particles deposition velocity decreased due to the increased velocity, and the reduction was progressively larger. Taking the first rough structure as an example, the partide-structure rebound angle increased by about 10 degrees as the air velocity increased by every 2 m/s. This work helps to clarify the deposition behaviors of fine particulate matter on rough surface, providing support for pipeline cleaning and engineering designs. (C) 2020 Elsevier B.V. All rights reserved.