Abstract Motion of small suspended particles in a turbulent channel flow is studied. The mean flow field is simulated using a two-equation κ-ε turbulence model. Trajectories of aerosol particles in the channel are evaluated by solving the corresponding Lagrangian equation of motion, which includes the effects of Brownian motion and turbulence fluctuations. Simulations are carried out for aerosol particles (of various sizes) released at different locations across the channel. Depositions of particles on the channel wall for several flow Reynolds numbers and different inlet turbulence intensity are evaluated. The results show that turbulence fluctuations dominate the particle dispersion and deposition processes. The deposition rate is shown to increase as the flow Reynolds number or the inlet flow turbulence intensity increases. The Brownian effects become significant for particles smaller than 1 μ.