A knowledge of bed shear stress induced by waves is required to understand dynamic processes of nearshore morphologies as a results of sediment transport. However, the information on the stress is still incomplete due to lack of measured data. The study analyzes the unsteady horizontally averaged shear stresses measured over mobile beds in a water tunnel. It is found from the analysis that the presence of the third and fifth harmonics in the shear stress is in good agreement with the measured concentration of suspended sediments.