The invention relates to a hydraulic accumulator with an accumulator housing provided in the form of a tube (1), inside of which a separating element, preferably a separating piston (9), which can be displaced in the axial direction (7) of the tube, separates pressure chambers (13, 15) located on either side of the separating piston. In addition, the tube (1) is closed at at least one end by a cover-like closing part (5) having a contact surface for joining to the respective end edge of the tube (1). The contact surface has a flat part provided in the form of an annular surface (39), which projects inside the tube (1) and which serves to positively brace the tube wall against radial forces, and the contact surface has an annular surface (41), which extends in a radial direction and which serves to positively brace the tube wall against axial forces.