To grip a bottle 10 with approximately the same level of a gripping force and make axial centers O of the gripped bottles 10 correspond to each other even if a diameter of the bottle gripped by a gripper 2 varies.

Grip members 34 are mounted to tip sides of a pair of leaf springs 30 each having a fixed rear end, and energized by a coil spring 36 in a direction approaching each other. A positioning member 38 abutting on a radial inner side of a bottle 10 gripped by the grip members 34 for positioning is installed in the middle of the both grip members 34. An opening amount adjustment part 38c is arranged in the positioning member 38, and an interference part 34c interfering with the adjustment part 38c is arranged in the grip member 2. When the positioning member 38 is moved to the radial inner side, both the grip members 34 can be spread and opened.