Experimental results are presented concerning the boundary shear stress distribution in a rectangular compound section channel comprising rectangular main channel and two symmetrically disposed floodplains. Different dimensionless ratios of shear stress distributions are obtained and related to relevant parameters. The floodplains due to the momentum transfer between the deep section and floodplains has been investigated. Some important results concerning the uniformity of shear stress distribution which is significant in alluvial channels to state the possible locations of erosion and deposition have been presented.