Experiments of sediment transport were performed to investigate the characteristics of transportation on rib beds by using artificial ribs and spontaneously formed ribs. The transported sand from the head of channel was heaped in a pool to form a ridge by the flow with submerged jet in the case of artificial rib beds. The ridge in the pool was reduced in volume by the flow when the sediment supply from the upper pool reduced or ceased. Thus accumulation wave of sand slowly traveled to downstream with damping the height. On the other hand, the low flow on the spontaneously formed ribs ran through the crevices of a step to transport the sediment in a bed load state. So little stagnation of sediment transport system between them depended on the depth of the pools.