It is generally assumed that regional variations among earthenware from the latter third of the Middle Yayoi period onwards are becoming more distinctive in Hiroshima prefecture. Earthenware of the “Shiomachi type”, referred to as highly decorated, has also been unearthed in the northern part of Bingo (the eastern part of Hiroshima prefecture). In this study, I examined the difference of patterns found among wide-mouthed pots with bellied body (kame) from those areas. As a result, regional differences between patterns found in the Basen River basin and Saijō River basin, specifically regarding decorative combinations and pot shapes were revealed. These differences likely exist due to the different manufacturing techniques of the pots used in each area, particularly based on observations such as brush marks (hakeme) surface finishing and clay-joint marks in cross-sections. In general, manufacturers applied patterns on pottery to achieve visual effects in the course of usage. However, we should also consider the possibility that such applications on the surface were placed on items to denote the manufacturing process. And of course it needs to be examined why different decorations were applied on pottery based on observations of the actual materials from each region.