A waterproof sealing structure for a cable and a communication device are provided. The waterproof sealing structure includes: a cable inner core, a cable sheath, fastening structures, and an actuating mechanism, wherein the cable sheath is molded by one-time pouring outside the cable inner core, the cable sheath comprises an elongated sheath and disc-shaped sheaths, the disc-shaped sheaths are molded at end portions of the elongated sheath, the end portions of the cable inner core are connected to the actuating mechanism, ends of the actuating mechanism connected to the cable inner core are open, and the disc-shaped sheaths are sealed and fastened at the open ends of the actuating mechanism through the fastening structures.