Motion and trajectory of small particles in turbulent airflow are numerically studied to clarify a striped pattern deposition Layer. In the simulation, the striped deposition layers are considered as obstacles on a flat wall, and the turbulent airflow fields in a rectangular channel are calculated by the kappa-epsilon model. The equation of particle motion includes drag force, gravitational force, and shear-induced lift force. To simulate the random motion of particles in turbulent now, the Monte Carlo method Is also applied, and the particle trajectories are calculated with the Lagrangian method. The effects of the shape and size of the obstacle on the particle trajectory and the deposition on channel wall are analyzed, and the frequency distribution of deposited particles are discussed in detail; namely, the non-deposition section behind the obstacle is equivalent to the interval between striped deposition layers, which increases with obstacle height, air velocity, and particle diameter.