Size distribution parameters and mineralogical composition of South Canadian River channel sands remain essentially constant over approximately 650 mi. of river distance. Mean roundness, mean sphericity, and mean shape factor values of some minerals in the channel sediment increase downstream, while these values decrease for others. However, most minerals show no significant variation in these properties either downstream or between size grades. Quartz-feldspar ratio increases significantly downstream in only 2 size grades. A brief review of size distribution and particle morphology parameters is given.