The influence of solid particles on the flow characteristics of the boundary layer for cross flow over a tube has been experimentally studied. A phase-Doppler anemometer was used to measure the mean and fluctuation velocities of both phases. Two separate tests were conducted with two particle size ranges (30-60μm and 80-150μm) and the freestream velocity and solid mass loading ratio were fixed, allowing the effects of particle sizes on the shape of the mean velocity profile and on the turbulent intensity levels. The measureraents clearly demonstrated that the larger particles damped fluid turbulence. For the smaller particies, this damping effect was less noticeable. The measurements further showed a delay in the separation point for two phase turbulent cross flow over a tube.