An accumulator of the invention is provided with a safety mechanism for an emergency which releases an internal pressure of the housing to the oil port side so as to prevent the housing from being exploded by the internal pressure of the housing which comes to a higher pressure in an emergency, for example, occurrence of fire disaster. The safety mechanism for the emergency has a taper portion in a corner portion between the tubular portion and the end surface portion of the stay. The taper portion is buckled at its root position in the emergency. In the case that the taper portion is buckled, a pressure releasing flow path is formed between the bellows cap or the retained member and the taper portion as well as the bellows cap or the retained member and the end surface portion come away. The stay can be manufactured only by press molding.