A control apparatus for an unmanned transport machine for delivering a package from a departure location to a destination includes a trouble information acquiring unit configured to acquire trouble information, a selection requesting unit configured to request a recipient of the package to select one option among a plurality of delivery method options when the trouble information indicates trouble occurring on a delivery route from the departure location to the destination, a candidate destination selecting unit configured to select candidate destinations corresponding to the delivery method options based on a current location of the unmanned transport machine and map information, and a destination determining unit configured to determine a new destination selected from the candidate destinations in accordance with the selected option.