A component mounting system includes a component mounting apparatus, a data creating apparatus and a component arranging operation supporting apparatus. The component mounting apparatus mounts components on a substrate. The data creating apparatus creates component data for each component. The component arranging operation supporting apparatus includes an identification information acquiring unit that acquires component identification information given to the component supplying member, and a control unit which checks a component to be disposed in a position based on the component identification information. The control unit of the component arranging operation supporting apparatus performs a request for a creation of component data regarding an alternative component, and the data creating apparatus receives the request and creates the component data regarding the alternative component.