A control device includes: an image acquiring section that acquires image data of an image of a work target of the work machine； a feature recognizing section that recognizes a feature about at least one of (i) a type of the work target of the work machine, (ii) a number or density of the work target, (iii) a shape of the work target and (iv) an appearance of the work target after work, based on the image data acquired by the image acquiring section； and a control parameter deciding section that decides at least either (i) a parameter for controlling travel of the work machine or (ii) a parameter for controlling work of the work machine, based on the feature recognized by the feature recognizing section.
