Container consisting of synthetic resin

A synthetic resin container with a bottom structure in which a bottom portion uniformly and mildly deforms responsive to a change in the internal pressure, and exhibits pressure reducing/absorbing capability to reliably cope with even a large change in the internal pressure. The synthetic resin container forms, in the bottom portion thereof, an outer circumferential wall that is continuing from the body portion, an annular leg portion inclusive of a grounding portion and an inner circumferential wall, and a raised bottom portion positioned over the grounding portion on the inside of the inner circumferential wall of the leg portion, wherein the raised bottom portion is protruding downward beyond the root portion where the leg portion is continuing to the inner circumferential wall, a plurality of arcuate protuberances are formed in a spiral shape heading from the outer edge of the central portion of the raised bottom portion toward the outer circumferential side, and arcuate dents are formed among the arcuate protuberances that are neighboring each other.