A high-pressure container comprising: a body part having a liner formed in a cylindrical shape, and a reinforcement layer that is provided on an outer circumferential surface of the liner and reinforces the liner; and a cap inserted in the body part, the cap having a contact portion that is in abutting contact with an inner circumferential surface of the liner, a communicating portion that communicates an inside of the body part with an outside of the body part, characterised in a projecting portion (60, 30) that is pressed outward in radial directions of the body part, and bites into the reinforcement layer; the projecting portion (60, 30) of the cap has a first tapered portion and a second tapered portion on one side remote from the reinforcement layer, the first tapered portion being inclined inward in the radial directions of the body part, and the second tapered portion being inclined outward in the radial direction of the body part as viewed in a direction toward one side in an axial direction of the body part; the boundary between the first tapered portion and the second tapered portion is located at substantially the middle in the axial direction of the inner circumferential surface of the projection portion; and the cap includes a first pressing part that is in abutting contact with the first tapered portion and a second pressing part that is in abutting contact with the second tapered portion, the first and second pressing parts (34,39) being configured to press the projecting portion (60, 30) against the reinforcement layer, such that the projecting portion (60, 30) bites into the reinforcement layer. a body part having a liner formed in a cylindrical shape, and a reinforcement layer that is provided on an outer circumferential surface of the liner and reinforces the liner; and a cap inserted in the body part, the cap having a contact portion that is in abutting contact with an inner circumferential surface of the liner, a communicating portion that communicates an inside of the body part with an outside of the body part, characterised in a projecting portion (60, 30) that is pressed outward in radial directions of the body part, and bites into the reinforcement layer; the projecting portion (60, 30) of the cap has a first tapered portion and a second tapered portion on one side remote from the reinforcement layer, the first tapered portion being inclined inward in the radial directions of the body part, and the second tapered portion being inclined outward in the radial direction of the body part as viewed in a direction toward one side in an axial direction of the body part; the boundary between the first tapered portion and the second tapered portion is located at substantially the middle in the axial direction of the inner circumferential surface of the projection portion; and the cap includes a first pressing part that is in abutting contact with the first tapered portion and a second pressing part that is in abutting contact with the second tapered portion, the first and second pressing parts (34,39) being configured to press the projecting portion (60, 30) against the reinforcement layer, such that the projecting portion (60, 30) bites into the reinforcement layer.