A cap attachment-detachment device comprising: a rotation driver; a plurality of attachment-detachment portions corresponding to a plurality of containers; and a transmitter that transmits rotation of the rotation driver to the plurality of attachment-detachment portions, wherein each of the plurality of attachment-detachment portions includes an operation portion that moves in a first direction or a second direction that is opposite to the first direction in response to rotation of the rotation driver and rotates a cap to attach the cap to or detach the cap from a corresponding container, and a restricting portion that restricts a torque to be applied to the cap by the operation portion when the cap is attached to the container, and characterized in that the cap attachment-detachment device further comprises: a rotation detector that detects rotation of the operation portion; and a determiner that determines whether the cap is properly fastened to the container based on a result of detection by the rotation detector, wherein the rotation driver includes a drive pulse generator that generates a drive pulse, and an electric motor that is rotated based on a drive pulse generated by the drive pulse generator, and the determiner determines whether the cap is properly fastened to the container based on a count of drive pulses generated by the drive pulse generator and a result of detection by the rotation detector. a rotation driver; a plurality of attachment-detachment portions corresponding to a plurality of containers; and a transmitter that transmits rotation of the rotation driver to the plurality of attachment-detachment portions, wherein each of the plurality of attachment-detachment portions includes an operation portion that moves in a first direction or a second direction that is opposite to the first direction in response to rotation of the rotation driver and rotates a cap to attach the cap to or detach the cap from a corresponding container, and a restricting portion that restricts a torque to be applied to the cap by the operation portion when the cap is attached to the container, and characterized in that the cap attachment-detachment device further comprises: a rotation detector that detects rotation of the operation portion; and a determiner that determines whether the cap is properly fastened to the container based on a result of detection by the rotation detector, wherein the rotation driver includes a drive pulse generator that generates a drive pulse, and an electric motor that is rotated based on a drive pulse generated by the drive pulse generator, and the determiner determines whether the cap is properly fastened to the container based on a count of drive pulses generated by the drive pulse generator and a result of detection by the rotation detector. a rotation detector that detects rotation of the operation portion; and a determiner that determines whether the cap is properly fastened to the container based on a result of detection by the rotation detector, wherein the rotation driver includes a drive pulse generator that generates a drive pulse, and an electric motor that is rotated based on a drive pulse generated by the drive pulse generator, and the determiner determines whether the cap is properly fastened to the container based on a count of drive pulses generated by the drive pulse generator and a result of detection by the rotation detector. a drive pulse generator that generates a drive pulse, and an electric motor that is rotated based on a drive pulse generated by the drive pulse generator, and the determiner determines whether the cap is properly fastened to the container based on a count of drive pulses generated by the drive pulse generator and a result of detection by the rotation detector.