The purpose of this study was to allow fish to move upstream past barriers or difficult sections of passage, even on steep stream-type fishways. Therefore, the authors devised a roughness arrangement to raise the water depth in the fishway and reduce its flow velocity. Roughness was used as a group in the arrangement so as to expect afflux effects. Water depth was raised and the flow velocity was reduced around the roughness groups, which allowed fish to hold position and move upstream. Although rapid flow was locally formed in some spots in the fishway, its area was small, enabling the fish to move upstream sufficiently. The experimental results obtained in this study will be applied as a removable stream-type fishway to small channels, head constructions, and so on where fishways cannot be installed due to management.