<p>The bottle is provided with a base portion installed on the outer circumference brim of the bottom, a central recess installed inside the base portion and recessed toward the inside of the bottle, an annular wall portion installed between the base portion and the central recess and inclined so as to elevate gradually from the base portion to the central recess, and a plurality of ribs installed side by side at the annular wall portion in the circumferential direction of the bottom and protruding toward the inside of the bottle. The ribs are provided with a rising wall portion rising toward the inside of the bottle and an inclined wall portion inclined from the upper brim of the rising wall portion toward the lower brim of the rising wall portion of an adjacent rib. The rising wall portion is inclined more steeply than the inclined wall portion.</p>
