The invention provides a dry towing transporting float-on process of a floating production, storage and offloading device. The dry towing transporting float-on process of the floating production, storage and offloading device comprises the following steps of 1, doing preparation work before loading of a semi-submerged ship; 2, wetly towing the floating production, storage and offloading device toreach a float-on location; 3, carrying out longitudinal shipment float-on operation on the floating production, storage and offloading device; and 4, carrying out shipment fixing and dry towing transportation on the floating production, storage and offloading device. Under the cooperation of a semi-submerged ship buoyancy tank winch cable and a harbour tugboat, the floating production, storage andoffloading device is towed to be kept stable after being reaching a preset shipment position; by using laser alignment to monitor relative positions of the semi-submerged ship and the floating production, storage and offloading device, the semi-submerged ship floats to support the floating production, storage and offloading device till reaching transporting draft; by welding a shipment fixing piece, the dry towing transporting float-on operation of the floating production, storage and offloading device is finished, and the semi-submerged ship carries the floating production, storage and offloading device to realize dry towing transporting sailing; the floating production, storage and offloading device is transported by using the semi-submerged ship; the working period is shortened, the engineering cost is saved, and the safety is good.