A capping device comprising: a conveying mechanism that conveys a container; a capping head that has a chuck for holding a cap and attaches the cap to a mouth of the container being conveyed by the conveying mechanism; a servomotor that rotates the chuck of the capping head; an elevating mechanism that raises and lowers the capping head; and a control device that controls driving of the servomotor and the conveying mechanism, in which the capping head holding the cap at the chuck is configured to be lowered by the elevating mechanism while rotation of the chuck is started from a stop state by the servomotor, whereby the cap held by the chuck is rotated to be screwed onto the mouth of the container, wherein the capping device comprises a speed detection mechanism that detects conveying speed of the container conveyed by the conveying mechanism; and the control device is configured to postpone rotation start timing for rotating the servomotor in a case in which the conveying speed of the conveying mechanism detected by the speed detection mechanism is lower than a predetermined operation speed, wherein when the conveying mechanism conveys the container at the predetermined operation speed, the control device is configured to start rotating the servomotor at a moment at which the chuck of the capping head is being lowered by the elevating mechanism, and a threaded portion of the cap held by the chuck is not yet in contact with a threaded portion of the container, characterized in that when the conveying mechanism conveys the container at an operation speed lower than the predetermined operation speed, the control device is configured to start rotating the servomotor at a moment at which the chuck of the capping head has been lowered by the elevating mechanism, and the threaded portion of the cap held by the chuck is in contact with the threaded portion of the container. in which the capping head holding the cap at the chuck is configured to be lowered by the elevating mechanism while rotation of the chuck is started from a stop state by the servomotor, whereby the cap held by the chuck is rotated to be screwed onto the mouth of the container, wherein the capping device comprises a speed detection mechanism that detects conveying speed of the container conveyed by the conveying mechanism; and the control device is configured to postpone rotation start timing for rotating the servomotor in a case in which the conveying speed of the conveying mechanism detected by the speed detection mechanism is lower than a predetermined operation speed, wherein when the conveying mechanism conveys the container at the predetermined operation speed, the control device is configured to start rotating the servomotor at a moment at which the chuck of the capping head is being lowered by the elevating mechanism, and a threaded portion of the cap held by the chuck is not yet in contact with a threaded portion of the container, characterized in that when the conveying mechanism conveys the container at an operation speed lower than the predetermined operation speed, the control device is configured to start rotating the servomotor at a moment at which the chuck of the capping head has been lowered by the elevating mechanism, and the threaded portion of the cap held by the chuck is in contact with the threaded portion of the container.