A cable tidying device includes a bracket mounted to a cabinet, a bobbin for wrapping cables inserted into the cabinet, and a locating member for locating the bobbin. The bracket includes a positioning plate defining a positioning hole and a first groove surrounding the positioning hole. The bobbin includes a wrapping axis extending through the first groove, and a driving portion extending from the wrapping axis. The locating member includes a spine plate, a fixing portion, and a spring resisting between the fixing portion and the positioning plate. The spine plate includes a main body, a protruding post protruding from the main body, and a plurality of ratchets spaced from each other. The fixing portion is attached to the protruding post. The driving portion engages with a different ratchet to locate the bobbin in a different position of the first groove.