A component mounting system includes a component mounter group, a storage, and a loader. The storage is provided on an upstream side or a downstream side of the component mounter group and has a storage area in which multiple component supply devices are arranged and supported detachably. The loader automatically takes out and/or attach the component supply devices from and/or to the component mounters and the storage. When an occupancy state of the component supply device supported by the storage area reaches a predetermined high occupancy state, the control section of the component mounting system outputs at least one of a recovery urging warning for prompting recovery of the component supply devices supported by the storage area and a replenishment prohibition warning for prohibiting replenishment of the component supply device used in a next production or later onto the storage area.