The distribution of low-relief surfaces were studied in the Miyoshi-Shobara area, Hiroshima Prefecture. Two kinds of the low-relief surfaces are commonly known as Kibi surface (450-550 m) and Sera surface (300-450 m) and they are widely distribted in the Chugoku district. Except these surfaces, another two stairs of surface are recognized; Shobara and Miyoshi surface. The Shobara surface existed 250-280 m above the sea level and the Miyoshi surface near 220-240 m. Because they occur along the rivers, they genetically formed as river terrace eroding the Sera surface. The distribution of the Sera surface indicates that the Miyoshi-Shobara area is located in the basin area and the basin had been formed after the formation of the Sera surface.