A synthetic resin bottle has a grip assembled and fixed in an upright orientation to the center part of a concave region at the ear portion of a substantially cylindrical trunk portion of the bottle main body. A shoulder portion in the bottle main body has a lower circumferential wall with a truncated pyramid shape defined by a plurality of panels. A right/left center axis of a rear surface panel is placed at substantially at the center of the rear surface of the bottle main body. A center portion of each of the panels is formed as a protrusion having a convex shape gradually bulging outwards of the bottle main body.