The invention relates to a floating multifunctional signal tower for transmitting open sea information and a working method of the floating multifunctional signal tower. The floating multifunctional signal tower is provided with a lifting platform, wherein the lifting platform comprises a manned platform, a plurality of small pulleys, a large pulley, an out-of-tower rope and an in-tower rope; the plurality of small pulleys are divided into two groups, each group of small pulleys are fixed on the left and right sides of the signal tower through supports, one end of the out-of-tower rope is fixed on a control room and winds around one group of small pulleys, the large pulley and other group of small pulleys, the other end of the out-of-tower rope is fixed in the control room, and the large pulley is located on the part, connected between the two groups of small pulleys, of the out-of-tower rope; the lifting platform is fixed on the part winding around the two groups of small pulleys, of the out-of-tower rope, a position, supporting the large pulley, of the out-of-tower rope is vertically connected with one end of the in-tower rope, and the other end of the in-tower rope is connected with a first roller. The floating multifunctional signal tower is provided with the lifting platform, a worker can arrive at any height of the signal tower by the aid of the lifting platform, working of the worker is facilitated, and the safety is guaranteed.