Thispaper presents an ana/ysis of wall proxlmlty Influence on the flow generated by waves ln the neighbourhood of an horizontal cy/inder. For KC=6, two different flow regimes were found, wjfh gaps of O. 7 and 0.5 diameter. These ones may be understood by a distinct influence of the wall. The bed shear stress is clearly modified by the change ln flow regime. ln the upstreom and downstream regions of the cylinder, except under the cylinder, the maximum wall shear stress never exceeds Its undisturbed value, But, regions of sharp variations in the wafl shear stressmay induce eros/on.