Experiments were performed in which suspended sediment concentration in open-channel bounded shear flow was varied systematically while flow depth, slope, and discharge were held essentially constant. The effect of variation in suspended sediment concentration on velocity profile characteristics was investigated. The experiments showed that the Karman coefficient was independent of changes in suspended sediment concentration, while the Coles wake strength coefficient was very sensitive to such changes. The thickness of the logarithmic part of the velocity profile decreased as sediment concentration increased. The logarithmic parts of velocity profiles in sediment-suspending flow were shifted downward relative to control profiles in comparable clear-water flows.