A pressure accumulator includes a cylindrical body made of metal and configured to vaporize and store a liquefied gas in a storage space in the cylindrical body, a lid body having a through hole that allows a pipe to penetrate through the through hole, and being configured to close an opening end portion of the cylindrical body with a gap between the lid body and an inner peripheral surface of the cylindrical body, a sealing structure portion between an outer peripheral portion of the lid body and an inner peripheral portion of the cylindrical body, and a fixing part at the opening end portion of the cylindrical body, an outer peripheral surface of the fixing part being screw fastened to the inner peripheral surface of the cylindrical body to support and fix the lid body from an outer side of the lid body.