Synthetic resin blow molded bottle

A synthetic resin blow molded bottle including a cylindrical-shaped mouth, a shoulder that is contiguous with and below the mouth, a trunk that is contiguous with and below the shoulder, and a bottom that closes a lower end of the trunk, wherein

• a plurality of reduced pressure absorbing panel portions and a plurality of column portions are formed alternately in a circumferential direction in a region extending from the shoulder to the trunk,
• each of the plurality of column portions has a diameter that gradually increases downward in the shoulder and that remains substantially constant vertically in the trunk,
• each of the plurality of reduced pressure absorbing panel portions includes a pair of panel side edge portions, which is bent to an inner side of the bottle from the column portions adjacent thereto, a panel surface portion, which connects the pair of panel side edge portions, and a panel lower edge portion, which is bent to an outer side of the bottle from a lower end edge of the panel surface portion, and
• the panel surface portion of each of the plurality of reduced pressure absorbing panel portions includes a panel upper-side surface portion, whose diameter gradually increases downward, and a panel lower-side surface portion, which connects the panel upper-side surface portion and the panel lower edge portion and which has a substantially constant diameter vertically.